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/**

*Submitted for verification at BscScan.com on 2021-03-12

*Submitted for verification at BscScan.com on 2021-02-21

/**

*Submitted for verification at BscScan.com on 2021-02-20

pragma solidity 0.6.12;

// saltswap.finance

/**

* @dev Wrappers over Solidity's arithmetic operations with added overflow

* checks.

* Arithmetic operations in Solidity wrap on overflow. This can easily result

* in bugs, because programmers usually assume that an overflow raises an

* error, which is the standard behavior in high level programming languages.

* `SafeMath` restores this intuition by reverting the transaction when an

* operation overflows.

* Using this library instead of the unchecked operations eliminates an entire

* class of bugs, so it's recommended to use it always.

library SafeMath {

/**

* @dev Returns the addition of two unsigned integers, with an overflow flag.

* _Available since v3.4._

function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {

uint256 c = a + b;

if (c < a) return (false, 0);

return (true, c);

}

/**

* @dev Returns the substraction of two unsigned integers, with an overflow flag.

* _Available since v3.4._

function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {

if (b > a) return (false, 0);

return (true, a - b);

}

/**

* @dev Returns the multiplication of two unsigned integers, with an overflow flag.

* _Available since v3.4._

function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {

// Gas optimization: this is cheaper than requiring 'a' not being zero, but the

// benefit is lost if 'b' is also tested.

// See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522

if (a == 0) return (true, 0);

uint256 c = a * b;

if (c / a != b) return (false, 0);

return (true, c);

}

/**

* @dev Returns the division of two unsigned integers, with a division by zero flag.

* _Available since v3.4._

function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {

if (b == 0) return (false, 0);

return (true, a / b);

}

/**

* @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.

* _Available since v3.4._

function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {

if (b == 0) return (false, 0);

return (true, a % b);

}

/**

* @dev Returns the addition of two unsigned integers, reverting on

* overflow.

* Counterpart to Solidity's `+` operator.

* Requirements:

* - Addition cannot overflow.

function add(uint256 a, uint256 b) internal pure returns (uint256) {

uint256 c = a + b;

require(c >= a, "SafeMath: addition overflow");

return c;

}

/**

* @dev Returns the subtraction of two unsigned integers, reverting on

* overflow (when the result is negative).

* Counterpart to Solidity's `-` operator.

* Requirements:

* - Subtraction cannot overflow.

function sub(uint256 a, uint256 b) internal pure returns (uint256) {

return sub(a, b, "SafeMath: subtraction overflow");

require(b <= a, "SafeMath: subtraction overflow");

}

return a - b;

/**

* @dev Returns the subtraction of two unsigned integers, reverting with custom message on

* overflow (when the result is negative).

* Counterpart to Solidity's `-` operator.

* Requirements:

* - Subtraction cannot overflow.

function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {

require(b <= a, errorMessage);

uint256 c = a - b;

return c;

}

/**

* @dev Returns the multiplication of two unsigned integers, reverting on

* overflow.

* Counterpart to Solidity's `*` operator.

* Requirements:

* - Multiplication cannot overflow.

function mul(uint256 a, uint256 b) internal pure returns (uint256) {

// Gas optimization: this is cheaper than requiring 'a' not being zero, but the

if (a == 0) return 0;

// benefit is lost if 'b' is also tested.

// See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522

if (a == 0) {

return 0;

}

uint256 c = a * b;

require(c / a == b, "SafeMath: multiplication overflow");

return c;

}

/**

* @dev Returns the integer division of two unsigned integers. Reverts on

* @dev Returns the integer division of two unsigned integers, reverting on

* division by zero. The result is rounded towards zero.

* Counterpart to Solidity's `/` operator. Note: this function uses a

* `revert` opcode (which leaves remaining gas untouched) while Solidity

* uses an invalid opcode to revert (consuming all remaining gas).

* Requirements:

* - The divisor cannot be zero.

function div(uint256 a, uint256 b) internal pure returns (uint256) {

return div(a, b, "SafeMath: division by zero");

require(b > 0, "SafeMath: division by zero");

return a / b;

}

/**

* @dev Returns the integer division of two unsigned integers. Reverts with custom message on

* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),

* division by zero. The result is rounded towards zero.

* reverting when dividing by zero.

* Counterpart to Solidity's `/` operator. Note: this function uses a

* Counterpart to Solidity's `%` operator. This function uses a `revert`

* `revert` opcode (which leaves remaining gas untouched) while Solidity

* opcode (which leaves remaining gas untouched) while Solidity uses an

* uses an invalid opcode to revert (consuming all remaining gas).

* invalid opcode to revert (consuming all remaining gas).

* Requirements:

* - The divisor cannot be zero.

function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {

function mod(uint256 a, uint256 b) internal pure returns (uint256) {

require(b > 0, errorMessage);

require(b > 0, "SafeMath: modulo by zero");

uint256 c = a / b;

return a % b;

// assert(a == b * c + a % b); // There is no case in which this doesn't hold

}

return c;

/**

* @dev Returns the subtraction of two unsigned integers, reverting with custom message on

* overflow (when the result is negative).

* CAUTION: This function is deprecated because it requires allocating memory for the error

* message unnecessarily. For custom revert reasons use {trySub}.

* Counterpart to Solidity's `-` operator.

* Requirements:

* - Subtraction cannot overflow.

function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {

require(b <= a, errorMessage);

return a - b;

}

/**

* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),

* @dev Returns the integer division of two unsigned integers, reverting with custom message on

* Reverts when dividing by zero.

* division by zero. The result is rounded towards zero.

* Counterpart to Solidity's `%` operator. This function uses a `revert`

* CAUTION: This function is deprecated because it requires allocating memory for the error

* opcode (which leaves remaining gas untouched) while Solidity uses an

* message unnecessarily. For custom revert reasons use {tryDiv}.

* invalid opcode to revert (consuming all remaining gas).

* Counterpart to Solidity's `/` operator. Note: this function uses a

* `revert` opcode (which leaves remaining gas untouched) while Solidity

* uses an invalid opcode to revert (consuming all remaining gas).

* Requirements:

* - The divisor cannot be zero.

function mod(uint256 a, uint256 b) internal pure returns (uint256) {

function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {

return mod(a, b, "SafeMath: modulo by zero");

require(b > 0, errorMessage);

return a / b;

}

/**

* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),

* Reverts with custom message when dividing by zero.

* reverting with custom message when dividing by zero.

* CAUTION: This function is deprecated because it requires allocating memory for the error

* message unnecessarily. For custom revert reasons use {tryMod}.

* Counterpart to Solidity's `%` operator. This function uses a `revert`

* opcode (which leaves remaining gas untouched) while Solidity uses an

* invalid opcode to revert (consuming all remaining gas).

* Requirements:

* - The divisor cannot be zero.

function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {

require(b != 0, errorMessage);

require(b > 0, errorMessage);

return a % b;

}

interface IBEP20 {

/**

* @dev Returns the amount of tokens in existence.

function totalSupply() external view returns (uint256);

/**

* @dev Returns the token decimals.

function decimals() external view returns (uint8);

/**

* @dev Returns the token symbol.

function symbol() external view returns (string memory);

/**

* @dev Returns the token name.

function name() external view returns (string memory);

/**

* @dev Returns the bep token owner.

function getOwner() external view returns (address);

/**

* @dev Returns the amount of tokens owned by `account`.

function balanceOf(address account) external view returns (uint256);

/**

* @dev Moves `amount` tokens from the caller's account to `recipient`.

* Returns a boolean value indicating whether the operation succeeded.

* Emits a {Transfer} event.

function transfer(address recipient, uint256 amount) external returns (bool);

/**

* @dev Returns the remaining number of tokens that `spender` will be

* allowed to spend on behalf of `owner` through {transferFrom}. This is

* zero by default.

* This value changes when {approve} or {transferFrom} are called.

function allowance(address _owner, address spender) external view returns (uint256);

/**

* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.

* Returns a boolean value indicating whether the operation succeeded.

* IMPORTANT: Beware that changing an allowance with this method brings the risk

* that someone may use both the old and the new allowance by unfortunate

* transaction ordering. One possible solution to mitigate this race

* condition is to first reduce the spender's allowance to 0 and set the

* desired value afterwards:

* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729

* Emits an {Approval} event.

function approve(address spender, uint256 amount) external returns (bool);

/**

* @dev Moves `amount` tokens from `sender` to `recipient` using the

* allowance mechanism. `amount` is then deducted from the caller's

* allowance.

* Returns a boolean value indicating whether the operation succeeded.

* Emits a {Transfer} event.

function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

/**

* @dev Emitted when `value` tokens are moved from one account (`from`) to

* another (`to`).

* Note that `value` may be zero.

event Transfer(address indexed from, address indexed to, uint256 value);

/**

* @dev Emitted when the allowance of a `spender` for an `owner` is set by

* a call to {approve}. `value` is the new allowance.

event Approval(address indexed owner, address indexed spender, uint256 value);

}

/**

* @dev Collection of functions related to the address type

library Address {

/**

* @dev Returns true if `account` is a contract.

* [IMPORTANT]

* ====

* It is unsafe to assume that an address for which this function returns

* false is an externally-owned account (EOA) and not a contract.

* Among others, `isContract` will return false for the following

* types of addresses:

* - an externally-owned account

* - a contract in construction

* - an address where a contract will be created

* - an address where a contract lived, but was destroyed

* ====

function isContract(address account) internal view returns (bool) {

// This method relies on extcodesize, which returns 0 for contracts in

// construction, since the code is only stored at the end of the

// constructor execution.

uint256 size;

// solhint-disable-next-line no-inline-assembly

assembly { size := extcodesize(account) }

return size > 0;

}

/**

* @dev Replacement for Solidity's `transfer`: sends `amount` wei to

* `recipient`, forwarding all available gas and reverting on errors.

* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost

* of certain opcodes, possibly making contracts go over the 2300 gas limit

* imposed by `transfer`, making them unable to receive funds via

* `transfer`. {sendValue} removes this limitation.

* https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].

* IMPORTANT: because control is transferred to `recipient`, care must be

* taken to not create reentrancy vulnerabilities. Consider using

* {ReentrancyGuard} or the

* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].

function sendValue(address payable recipient, uint256 amount) internal {

require(address(this).balance >= amount, "Address: insufficient balance");

// solhint-disable-next-line avoid-low-level-calls, avoid-call-value

(bool success, ) = recipient.call{ value: amount }("");

require(success, "Address: unable to send value, recipient may have reverted");

}

/**

* @dev Performs a Solidity function call using a low level `call`. A

* plain`call` is an unsafe replacement for a function call: use this

* function instead.

* If `target` reverts with a revert reason, it is bubbled up by this

* function (like regular Solidity function calls).

* Returns the raw returned data. To convert to the expected return value,

* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].

* Requirements:

* - `target` must be a contract.

* - calling `target` with `data` must not revert.

* _Available since v3.1._

function functionCall(address target, bytes memory data) internal returns (bytes memory) {

return functionCall(target, data, "Address: low-level call failed");

}

/**

* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with

* `errorMessage` as a fallback revert reason when `target` reverts.

* _Available since v3.1._

function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {

return functionCallWithValue(target, data, 0, errorMessage);

}

/**

* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],

* but also transferring `value` wei to `target`.

* Requirements:

* - the calling contract must have an ETH balance of at least `value`.

* - the called Solidity function must be `payable`.

* _Available since v3.1._

function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {

return functionCallWithValue(target, data, value, "Address: low-level call with value failed");

}

/**

* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but

* with `errorMessage` as a fallback revert reason when `target` reverts.

* _Available since v3.1._

function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {

require(address(this).balance >= value, "Address: insufficient balance for call");

require(isContract(target), "Address: call to non-contract");

// solhint-disable-next-line avoid-low-level-calls

(bool success, bytes memory returndata) = target.call{ value: value }(data);

return _verifyCallResult(success, returndata, errorMessage);

}

/**

* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],

* but performing a static call.

* _Available since v3.3._

function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {

return functionStaticCall(target, data, "Address: low-level static call failed");

}

/**

* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],

* but performing a static call.

* _Available since v3.3._

function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {

require(isContract(target), "Address: static call to non-contract");

// solhint-disable-next-line avoid-low-level-calls

(bool success, bytes memory returndata) = target.staticcall(data);

return _verifyCallResult(success, returndata, errorMessage);

}

/**

* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],

* but performing a delegate call.

* _Available since v3.4._

function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {

return functionDelegateCall(target, data, "Address: low-level delegate call failed");

}

/**

* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],

* but performing a delegate call.

* _Available since v3.4._

function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {

require(isContract(target), "Address: delegate call to non-contract");

// solhint-disable-next-line avoid-low-level-calls

(bool success, bytes memory returndata) = target.delegatecall(data);

return _verifyCallResult(success, returndata, errorMessage);

}

function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {

if (success) {

return returndata;

} else {

// Look for revert reason and bubble it up if present

if (returndata.length > 0) {

// The easiest way to bubble the revert reason is using memory via assembly

// solhint-disable-next-line no-inline-assembly

assembly {

let returndata_size := mload(returndata)

revert(add(32, returndata), returndata_size)

}

} else {

revert(errorMessage);

}

/**

* @title SafeBEP20

* @dev Wrappers around BEP20 operations that throw on failure (when the token

* contract returns false). Tokens that return no value (and instead revert or

* throw on failure) are also supported, non-reverting calls are assumed to be

* successful.

* To use this library you can add a `using SafeBEP20 for IBEP20;` statement to your contract,

* which allows you to call the safe operations as `token.safeTransfer(...)`, etc.

library SafeBEP20 {

using SafeMath for uint256;

using Address for address;

function safeTransfer(IBEP20 token, address to, uint256 value) internal {

_callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));

}

function safeTransferFrom(IBEP20 token, address from, address to, uint256 value) internal {

_callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));

}

/**

* @dev Deprecated. This function has issues similar to the ones found in

* {IBEP20-approve}, and its usage is discouraged.

* Whenever possible, use {safeIncreaseAllowance} and

* {safeDecreaseAllowance} instead.

function safeApprove(IBEP20 token, address spender, uint256 value) internal {

// safeApprove should only be called when setting an initial allowance,

// or when resetting it to zero. To increase and decrease it, use

// 'safeIncreaseAllowance' and 'safeDecreaseAllowance'

// solhint-disable-next-line max-line-length

require((value == 0) || (token.allowance(address(this), spender) == 0),

"SafeBEP20: approve from non-zero to non-zero allowance"

);

_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));

}

function safeIncreaseAllowance(IBEP20 token, address spender, uint256 value) internal {

uint256 newAllowance = token.allowance(address(this), spender).add(value);

_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));

}

function safeDecreaseAllowance(IBEP20 token, address spender, uint256 value) internal {

uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeBEP20: decreased allowance below zero");

_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));

}

/**

* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement

* on the return value: the return value is optional (but if data is returned, it must not be false).

* @param token The token targeted by the call.

* @param data The call data (encoded using abi.encode or one of its variants).

function _callOptionalReturn(IBEP20 token, bytes memory data) private {

// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since

// we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that

// the target address contains contract code and also asserts for success in the low-level call.

bytes memory returndata = address(token).functionCall(data, "SafeBEP20: low-level call failed");

if (returndata.length > 0) { // Return data is optional

// solhint-disable-next-line max-line-length

require(abi.decode(returndata, (bool)), "SafeBEP20: BEP20 operation did not succeed");

}

interface IPancakePair {

function token0() external view returns (address);

function token1() external view returns (address);

}

interface IUniswapV2Router02 {

function factory() external pure returns (address);

function WETH() external pure returns (address);

function swapExactTokensForTokens(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline) external returns (uint[] memory amounts);

function addLiquidity(address tokenA,address tokenB,uint amountADesired,uint amountBDesired,uint amountAMin,uint amountBMin,address to,uint deadline) external returns (uint amountA, uint amountB, uint liquidity);

function removeLiquidity(address tokenA,address tokenB,uint liquidity,uint amountAMin,uint amountBMin,address to,uint deadline) external returns (uint amountA, uint amountB);

}

interface IUniswapV2Factory {

function getPair(address tokenA, address tokenB) external view returns (address pair);

function createPair(address tokenA, address tokenB) external returns (address pair);

}

* @dev Provides information about the current execution context, including the

* sender of the transaction and its data. While these are generally available

* via msg.sender and msg.data, they should not be accessed in such a direct

* manner, since when dealing with GSN meta-transactions the account sending and

* paying for execution may not be the actual sender (as far as an application

* is concerned).

* This contract is only required for intermediate, library-like contracts.

abstract contract Context {

function _msgSender() internal view virtual returns (address payable) {

return msg.sender;

}

function _msgData() internal view virtual returns (bytes memory) {

this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691

return msg.data;

}

/**

* @dev Contract module which provides a basic access control mechanism, where

* there is an account (an owner) that can be granted exclusive access to

* specific functions.

* By default, the owner account will be the one that deploys the contract. This

* can later be changed with {transferOwnership}.

* This module is used through inheritance. It will make available the modifier

* `onlyOwner`, which can be applied to your functions to restrict their use to

* the owner.

abstract contract Ownable is Context {

address private _owner;

event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

/**

* @dev Initializes the contract setting the deployer as the initial owner.

constructor () internal {

address msgSender = _msgSender();

_owner = msgSender;

emit OwnershipTransferred(address(0), msgSender);

}

/**

* @dev Returns the address of the current owner.

function owner() public view returns (address) {

function owner() public view virtual returns (address) {

return _owner;

}

/**

* @dev Throws if called by any account other than the owner.

modifier onlyOwner() {

require(_owner == _msgSender(), "Ownable: caller is not the owner");

require(owner() == _msgSender(), "Ownable: caller is not the owner");

}

/**

* @dev Leaves the contract without owner. It will not be possible to call

* `onlyOwner` functions anymore. Can only be called by the current owner.

* NOTE: Renouncing ownership will leave the contract without an owner,

* thereby removing any functionality that is only available to the owner.

function renounceOwnership() public virtual onlyOwner {

emit OwnershipTransferred(_owner, address(0));

_owner = address(0);

}

/**

* @dev Transfers ownership of the contract to a new account (`newOwner`).

* Can only be called by the current owner.

function transferOwnership(address newOwner) public virtual onlyOwner {

require(newOwner != address(0), "Ownable: new owner is the zero address");

emit OwnershipTransferred(_owner, newOwner);

_owner = newOwner;

}

/**

* @dev Implementation of the {IBEP20} interface.

* This implementation is agnostic to the way tokens are created. This means

* that a supply mechanism has to be added in a derived contract using {_mint}.

* For a generic mechanism see {BEP20PresetMinterPauser}.

* For a generic mechanism see {BEP20PresetM

* TIP: For a detailed writeup see our guide

* https://forum.zeppelin.solutions/t/how-to-implement-BEP20-supply-mechanisms/226[How

* to implement supply mechanisms].

* We have followed general OpenZeppelin guidelines: functions revert instead

* of returning `false` on failure. This behavior is nonetheless conventional

* and does not conflict with the expectations of BEP20 applications.

* Additionally, an {Approval} event is emitted on calls to {transferFrom}.

* This allows applications to reconstruct the allowance for all accounts just

* by listening to said events. Other implementations of the EIP may not emit

* these events, as it isn't required by the specification.

* Finally, the non-standard {decreaseAllowance} and {increaseAllowance}

* functions have been added to mitigate the well-known issues around setting

* allowances. See {IBEP20-approve}.

contract BEP20 is Context, IBEP20, Ownable {

using SafeMath for uint256;

mapping(address => uint256) private _balances;

mapping(address => mapping(address => uint256)) private _allowances;

uint256 private _totalSupply;

string private _name;

string private _symbol;

uint8 private _decimals;

/**

* @dev Sets the values for {name} and {symbol}, initializes {decimals} with

* a default value of 18.

* To select a different value for {decimals}, use {_setupDecimals}.

* All three of these values are immutable: they can only be set once during

* construction.

constructor(string memory name, string memory symbol) public {

_name = name;

_symbol = symbol;

_decimals = 18;

}

/**

* @dev Returns the bep token owner.

function getOwner() external override view returns (address) {

return owner();

}

/**

* @dev Returns the name of the token.

function name() public override view returns (string memory) {

return _name;

}

/**

* @dev Returns the symbol of

Saved diffs

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Open file

 /**
 *Submitted for verification at BscScan.com on 2021-03-12
*/

pragma solidity 0.6.12;


// 
/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return div(a, b, "SafeMath: division by zero");
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return mod(a, b, "SafeMath: modulo by zero");
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts with custom message when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}

interface IBEP20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the token decimals.
     */
    function decimals() external view returns (uint8);

    /**
     * @dev Returns the token symbol.
     */
    function symbol() external view returns (string memory);

    /**
     * @dev Returns the token name.
     */
    function name() external view returns (string memory);

    /**
     * @dev Returns the bep token owner.
     */
    function getOwner() external view returns (address);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address _owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

// 
/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain`call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
      return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: value }(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

// 
/**
 * @title SafeBEP20
 * @dev Wrappers around BEP20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeBEP20 for IBEP20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeBEP20 {
    using SafeMath for uint256;
    using Address for address;

    function safeTransfer(IBEP20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(IBEP20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IBEP20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(IBEP20 token, address spender, uint256 value) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        // solhint-disable-next-line max-line-length
        require((value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeBEP20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

    function safeIncreaseAllowance(IBEP20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).add(value);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    function safeDecreaseAllowance(IBEP20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeBEP20: decreased allowance below zero");
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IBEP20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.

        bytes memory returndata = address(token).functionCall(data, "SafeBEP20: low-level call failed");
        if (returndata.length > 0) { // Return data is optional
            // solhint-disable-next-line max-line-length
            require(abi.decode(returndata, (bool)), "SafeBEP20: BEP20 operation did not succeed");
        }
    }
}

interface IPancakePair {
    function token0() external view returns (address);
    function token1() external view returns (address);
}

interface IUniswapV2Router02 {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);
    function swapExactTokensForTokens(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline) external returns (uint[] memory amounts);

    function addLiquidity(address tokenA,address tokenB,uint amountADesired,uint amountBDesired,uint amountAMin,uint amountBMin,address to,uint deadline) external returns (uint amountA, uint amountB, uint liquidity);
    function removeLiquidity(address tokenA,address tokenB,uint liquidity,uint amountAMin,uint amountBMin,address to,uint deadline) external returns (uint amountA, uint amountB);
}

interface IUniswapV2Factory {
    function getPair(address tokenA, address tokenB) external view returns (address pair);
    function createPair(address tokenA, address tokenB) external returns (address pair);
}

// 
/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address payable) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

// 
/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor () internal {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(_owner == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

/**
 * @dev Implementation of the {IBEP20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {BEP20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-BEP20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin guidelines: functions revert instead
 * of returning `false` on failure. This behavior is nonetheless conventional
 * and does not conflict with the expectations of BEP20 applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IBEP20-approve}.
 */
contract BEP20 is Context, IBEP20, Ownable {
    using SafeMath for uint256;

    mapping(address => uint256) private _balances;

    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;
    uint8 private _decimals;

    /**
     * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
     * a default value of 18.
     *
     * To select a different value for {decimals}, use {_setupDecimals}.
     *
     * All three of these values are immutable: they can only be set once during
     * construction.
     */
    constructor(string memory name, string memory symbol) public {
        _name = name;
        _symbol = symbol;
        _decimals = 18;
    }

    /**
     * @dev Returns the bep token owner.
     */
    function getOwner() external override view returns (address) {
        return owner();
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public override view returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public override view returns (string memory) {
        return _symbol;
    }

    /**
    * @dev Returns the number of decimals used to get its user representation.
    */
    function decimals() public override view returns (uint8) {
        return _decimals;
    }

    /**
     * @dev See {BEP20-totalSupply}.
     */
    function totalSupply() public override view returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {BEP20-balanceOf}.
     */
    function balanceOf(address account) public override view returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev See {BEP20-transfer}.
     *
     * Requirements:
     *
     * - `recipient` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address recipient, uint256 amount) public override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    /**
     * @dev See {BEP20-allowance}.
     */
    function allowance(address owner, address spender) public override view returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {BEP20-approve}.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }

    /**
     * @dev See {BEP20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {BEP20};
     *
     * Requirements:
     * - `sender` and `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     * - the caller must have allowance for `sender`'s tokens of at least
     * `amount`.
     */
    function transferFrom (address sender, address recipient, uint256 amount) public override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(
            sender,
            _msgSender(),
            _allowances[sender][_msgSender()].sub(amount, 'BEP20: transfer amount exceeds allowance')
        );
        return true;
    }

    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {BEP20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
        return true;
    }

    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {BEP20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, 'BEP20: decreased allowance below zero'));
        return true;
    }

    /**
     * @dev Creates `amount` tokens and assigns them to `msg.sender`, increasing
     * the total supply.
     *
     * Requirements
     *
     * - `msg.sender` must be the token owner
     */
    function mint(uint256 amount) public onlyOwner returns (bool) {
        _mint(_msgSender(), amount);
        return true;
    }

    /**
     * @dev Moves tokens `amount` from `sender` to `recipient`.
     *
     * This is internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `sender` cannot be the zero address.
     * - `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     */
    function _transfer (address sender, address recipient, uint256 amount) internal {
        require(sender != address(0), 'BEP20: transfer from the zero address');
        require(recipient != address(0), 'BEP20: transfer to the zero address');

        _balances[sender] = _balances[sender].sub(amount, 'BEP20: transfer amount exceeds balance');
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }

    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements
     *
     * - `to` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal {
        require(account != address(0), 'BEP20: mint to the zero address');

        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        emit Transfer(address(0), account, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal {
        require(account != address(0), 'BEP20: burn from the zero address');

        _balances[account] = _balances[account].sub(amount, 'BEP20: burn amount exceeds balance');
        _totalSupply = _totalSupply.sub(amount);
        emit Transfer(account, address(0), amount);
    }

    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner`s tokens.
     *
     * This is internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve (address owner, address spender, uint256 amount) internal {
        require(owner != address(0), 'BEP20: approve from the zero address');
        require(spender != address(0), 'BEP20: approve to the zero address');

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`.`amount` is then deducted
     * from the caller's allowance.
     *
     * See {_burn} and {_approve}.
     */
    function _burnFrom(address account, uint256 amount) internal {
        _burn(account, amount);
        _approve(account, _msgSender(), _allowances[account][_msgSender()].sub(amount, 'BEP20: burn amount exceeds allowance'));
    }
}

contract DinoToken is BEP20('Dino Token', 'DINO') {

    function mint(address _to, uint256 _amount) public onlyOwner {
        _mint(_to, _amount);
    }

    function mint2(address _to, uint256 _amount) public onlyOwner {
        _mint(_to, _amount);
    }    
}

// 
// import "hardhat/console.sol";
// MasterChef is the master of Dino. He can make Dino and he is a fair guy.
//
// Note that it's ownable and the owner wields tremendous power. The ownership
// will be transferred to a governance smart contract once DINO is sufficiently
// distributed and the community can show to govern itself.
//
// Have fun reading it. Hopefully it's bug-free. God bless.
contract MasterChefAuto is Ownable {
    using SafeMath for uint256;
    using SafeBEP20 for IBEP20;

    // Info of each user.
    struct UserInfo {
        uint256 amount;         // How many LP tokens the user has provided.
        uint256 rewardDebt;     // Reward debt. See explanation below.
        //
        // We do some fancy math here. Basically, any point in time, the amount of DINOs
        // entitled to a user but is pending to be distributed is:
        //
        //   pending reward = (user.amount * pool.accDinoPerShare) - user.rewardDebt
        //
        // Whenever a user deposits or withdraws LP tokens to a pool. Here's what happens:
        //   1. The pool's `accDinoPerShare` (and `lastRewardBlock`) gets updated.
        //   2. User receives the pending reward sent to his/her address.
        //   3. User's `amount` gets updated.
        //   4. User's `rewardDebt` gets updated.
    }

    // Info of each pool.
    struct PoolInfo {
        IBEP20 lpToken;           // Address of LP token contract.
        bool isLp;                // whether this is an LP or just a regular erc20 staking token
        uint256 allocPoint;       // How many allocation points assigned to this pool. DINOs to distribute per block.
        uint256 lastRewardBlock;  // Last block number that DINOs distribution occurs.
        uint256 accDinoPerShare;   // Accumulated DINOs per share, times 1e12. See below.
        uint16 depositFeeBP;      // Deposit fee in basis points
    }

    // The DINO TOKEN!
    DinoToken public dino;
    // Dev address.
    address public devaddr;
    // DINO tokens created per block.
    uint256 public dinoPerBlock;
    // Bonus muliplier for early dino makers.
    uint256 public constant BONUS_MULTIPLIER = 1;
    // Deposit Fee address
    address public feeAddress;

    // Info of each pool.
    PoolInfo[] public poolInfo;
    // Info of each user that stakes LP tokens.
    mapping (uint256 => mapping (address => UserInfo)) public userInfo;
    // Total allocation points. Must be the sum of all allocation points in all pools.
    uint256 public totalAllocPoint = 0;

    // The block number when DINO mining starts.
    uint256 public startBlock;

    // Whether auto-buybacks are active or not
    bool public autoBuyback;

    IUniswapV2Router02 public pancakeRouter;
    IUniswapV2Factory public pancakeFactory;
    address public busd;
    address public bnb;

    event Deposit(address indexed user, uint256 indexed pid, uint256 amount);
    event Withdraw(address indexed user, uint256 indexed pid, uint256 amount);
    event EmergencyWithdraw(address indexed user, uint256 indexed pid, uint256 amount);

    constructor(
        DinoToken _dino,
        address _devaddr,
        address _feeAddress,
        uint256 _dinoPerBlock,

        address _router,
        address _busd
    ) public {
        dino = _dino;
        devaddr = _devaddr;
        feeAddress = _feeAddress;
        dinoPerBlock = _dinoPerBlock;

        pancakeRouter = IUniswapV2Router02(_router != address(0) ? _router : 0x05fF2B0DB69458A0750badebc4f9e13aDd608C7F); // test
        pancakeFactory = IUniswapV2Factory(pancakeRouter.factory());
        bnb = pancakeRouter.WETH();
        busd = _busd != address(0) ? _busd : 0xe9e7CEA3DedcA5984780Bafc599bD69ADd087D56;
    }

    function poolLength() external view returns (uint256) {
        return poolInfo.length;
    }

    function setStartBlock(uint256 _startBlock) public onlyOwner {
        require(startBlock == 0, "already started");
        startBlock = _startBlock;
    }

    function setAutobuyback(bool _autoBuyback) public onlyOwner {
        autoBuyback = _autoBuyback;
    }    

    // Add a new lp to the pool. Can only be called by the owner.
    // XXX DO NOT add the same LP token more than once. Rewards will be messed up if you do.
    function add(uint256 _allocPoint, IBEP20 _lpToken, bool _isLp, uint16 _depositFeeBP, bool _withUpdate) public onlyOwner {
        require(_depositFeeBP <= 10000, "add: invalid deposit fee basis points");
        if (_withUpdate) {
            massUpdatePools();
        }
        uint256 lastRewardBlock = block.number > startBlock ? block.number : startBlock;
        totalAllocPoint = totalAllocPoint.add(_allocPoint);
        poolInfo.push(PoolInfo({
            lpToken: _lpToken,
            isLp: _isLp,
            allocPoint: _allocPoint,
            lastRewardBlock: lastRewardBlock,
            accDinoPerShare: 0,
            depositFeeBP: _depositFeeBP
        }));
    }

    // Update the given pool's DINO allocation point and deposit fee. Can only be called by the owner.
    function set(uint256 _pid, uint256 _allocPoint, uint16 _depositFeeBP, bool _withUpdate) public onlyOwner {
        require(_depositFeeBP <= 10000, "set: invalid deposit fee basis points");
        if (_withUpdate) {
            massUpdatePools();
        }
        totalAllocPoint = totalAllocPoint.sub(poolInfo[_pid].allocPoint).add(_allocPoint);
        poolInfo[_pid].allocPoint = _allocPoint;
        poolInfo[_pid].depositFeeBP = _depositFeeBP;
    }

    // Return reward multiplier over the given _from to _to block.
    function getMultiplier(uint256 _from, uint256 _to) public pure returns (uint256) {
        return _to.sub(_from).mul(BONUS_MULTIPLIER);
    }

    // View function to see pending DINOs on frontend.
    function pendingDino(uint256 _pid, address _user) external view returns (uint256) {
        PoolInfo storage pool = poolInfo[_pid];
        UserInfo storage user = userInfo[_pid][_user];
        uint256 accDinoPerShare = pool.accDinoPerShare;
        uint256 lpSupply = pool.lpToken.balanceOf(address(this));
        if (block.number > pool.lastRewardBlock && lpSupply != 0) {
            uint256 multiplier = getMultiplier(pool.lastRewardBlock, block.number);
            uint256 dinoReward = multiplier.mul(dinoPerBlock).mul(pool.allocPoint).div(totalAllocPoint);
            accDinoPerShare = accDinoPerShare.add(dinoReward.mul(1e12).div(lpSupply));
        }
        return user.amount.mul(accDinoPerShare).div(1e12).sub(user.rewardDebt);
    }

    // Update reward variables for all pools. Be careful of gas spending!
    function massUpdatePools() public {
        uint256 length = poolInfo.length;
        for (uint256 pid = 0; pid < length; ++pid) {
            updatePool(pid);
        }
    }

    // Update reward variables of the given pool to be up-to-date.
    function updatePool(uint256 _pid) public {
        PoolInfo storage pool = poolInfo[_pid];
        if (block.number <= pool.lastRewardBlock) {
            return;
        }
        uint256 lpSupply = pool.lpToken.balanceOf(address(this));
        if (lpSupply == 0 || pool.allocPoint == 0) {
            pool.lastRewardBlock = block.number;
            return;
        }
        uint256 multiplier = getMultiplier(pool.lastRewardBlock, block.number);
        uint256 dinoReward = multiplier.mul(dinoPerBlock).mul(pool.allocPoint).div(totalAllocPoint);
        dino.mint(devaddr, dinoReward.div(10));
        dino.mint(address(this), dinoReward);
        pool.accDinoPerShare = pool.accDinoPerShare.add(dinoReward.mul(1e12).div(lpSupply));
        pool.lastRewardBlock = block.number;
    }

    // Deposit LP tokens to MasterChef for DINO allocation.
    function deposit(uint256 _pid, uint256 _amount) public {
        require(startBlock != 0 && block.number >= startBlock, "did not start yet");
        PoolInfo storage pool = poolInfo[_pid];
        UserInfo storage user = userInfo[_pid][msg.sender];
        updatePool(_pid);
        if (user.amount > 0) {
            uint256 pending = user.amount.mul(pool.accDinoPerShare).div(1e12).sub(user.rewardDebt);
            if (pending > 0) {
                safeDinoTransfer(msg.sender, pending);
            }
        }
        if (_amount > 0) {
            pool.lpToken.safeTransferFrom(address(msg.sender), address(this), _amount);
            if (pool.depositFeeBP > 0) {
                uint256 depositFee = _amount.mul(pool.depositFeeBP).div(10000);
                if (autoBuyback) {
                    uint256 devFee = depositFee.div(4);
                    pool.lpToken.safeTransfer(feeAddress, devFee);
                    if (pool.isLp) {
                        _processDepositFeeLP(pool.lpToken, depositFee.sub(devFee));
                    } else {
                        _processDepositFeeSingleAsset(pool.lpToken, depositFee.sub(devFee));
                    }
                } else {
                    pool.lpToken.safeTransfer(feeAddress, depositFee);
                }
                user.amount = user.amount.add(_amount).sub(depositFee);
            } else {
                user.amount = user.amount.add(_amount);
            }
        }
        user.rewardDebt = user.amount.mul(pool.accDinoPerShare).div(1e12);
        emit Deposit(msg.sender, _pid, _amount);
    }

    // Withdraw LP tokens from MasterChef.
    function withdraw(uint256 _pid, uint256 _amount) public {
        PoolInfo storage pool = poolInfo[_pid];
        UserInfo storage user = userInfo[_pid][msg.sender];
        require(user.amount >= _amount, "withdraw: not good");
        updatePool(_pid);
        uint256 pending = user.amount.mul(pool.accDinoPerShare).div(1e12).sub(user.rewardDebt);
        if (pending > 0) {
            safeDinoTransfer(msg.sender, pending);
        }
        if (_amount > 0) {
            user.amount = user.amount.sub(_amount);
            pool.lpToken.safeTransfer(address(msg.sender), _amount);
        }
        user.rewardDebt = user.amount.mul(pool.accDinoPerShare).div(1e12);
        emit Withdraw(msg.sender, _pid, _amount);
    }

    // Withdraw without caring about rewards. EMERGENCY ONLY.
    function emergencyWithdraw(uint256 _pid) public {
        PoolInfo storage pool = poolInfo[_pid];
        UserInfo storage user = userInfo[_pid][msg.sender];
        uint256 amount = user.amount;
        user.amount = 0;
        user.rewardDebt = 0;
        pool.lpToken.safeTransfer(address(msg.sender), amount);
        emit EmergencyWithdraw(msg.sender, _pid, amount);
    }

    // Safe dino transfer function, just in case if rounding error causes pool to not have enough DINOs.
    function safeDinoTransfer(address _to, uint256 _amount) internal {
        uint256 dinoBal = dino.balanceOf(address(this));
        if (_amount > dinoBal) {
            dino.transfer(_to, dinoBal);
        } else {
            dino.transfer(_to, _amount);
        }
    }

    // Update dev address by the previous dev.
    function dev(address _devaddr) public {
        require(msg.sender == devaddr, "dev: wut?");
        devaddr = _devaddr;
    }

    function setFeeAddress(address _feeAddress) public{
        require(msg.sender == feeAddress, "setFeeAddress: FORBIDDEN");
        feeAddress = _feeAddress;
    }

    //Pancake has to add hidden dummy pools inorder to alter the emission, here we make it simple and transparent to all.
    function updateEmissionRate(uint256 _dinoPerBlock) public onlyOwner {
        massUpdatePools();
        dinoPerBlock = _dinoPerBlock;
    }

    function _swap(address from, address to, uint256 amt) internal returns (uint256) {
        if (from == to) {
            return amt;
        }
        address pair = pancakeFactory.getPair(from, to);
        // if there is no direct pair, route through bnb, that's the assumption here
        if (pair == address(0)) {
            address[] memory path = new address[](3);
            path[0] = from;
            path[1] = pancakeRouter.WETH();
            path[2] = to;
            uint256[] memory amts = pancakeRouter.swapExactTokensForTokens(amt,0,path,address(this),block.timestamp);
            return amts[amts.length - 1];
        } else {
            address[] memory path = new address[](2);
            path[0] = from;
            path[1] = to;
            // console.log("swapping from %s to %s with amt %s", from, to, amt);
            uint256[] memory amts = pancakeRouter.swapExactTokensForTokens(amt,0,path,address(this),block.timestamp);
            return amts[amts.length - 1];
        }
    }

    //
    // Cool function, right? Hope it's not bugged. If it is, email Vitalik or contact flexartist@protonmail.com
    //
    function _processDepositFeeLP(IBEP20 _lpAddress, uint256 _depositFee) internal {
        address _dino = address(dino);

        // 1. Remove given amount of LP tokens
        _lpAddress.safeApprove(address(pancakeRouter), 0);
        _lpAddress.safeApprove(address(pancakeRouter), _depositFee);

        IPancakePair p = IPancakePair(address(_lpAddress));
        address tok0 = p.token0();
        address tok1 = p.token1();
        (tok0, tok1) = (tok0 == pancakeRouter.WETH()) ? (tok1,tok0) : (tok0,tok1);
        (uint amt0, uint amt1) = pancakeRouter.removeLiquidity(tok0, tok1, _depositFee, 0, 0, address(this), block.timestamp);

        // 2. Dump both tokens from the LP to DINO
        IBEP20(tok0).safeApprove(address(pancakeRouter), 0);
        IBEP20(tok0).safeApprove(address(pancakeRouter), amt0);
        IBEP20(tok1).safeApprove(address(pancakeRouter), 0);
        IBEP20(tok1).safeApprove(address(pancakeRouter), amt1);
        uint256 amtDinoBought = _swap(tok0, _dino, amt0).add(_swap(tok1, _dino, amt1));
        // console.log("dino bought", amtDinoBought);

        // 3. Dump 1/4 DINO to BUSD and 1/4 to BNB to add to liquidity
        IBEP20(_dino).safeApprove(address(pancakeRouter), 0);
        IBEP20(_dino).safeApprove(address(pancakeRouter), uint(-1));
        uint256 amtBusdLiquidity = _swap(_dino, busd, amtDinoBought.div(4));
        uint256 amtBnbLiquidity = _swap(_dino, bnb, amtDinoBought.div(4));
        // console.log("amtBusdLiquidity", amtBusdLiquidity);
        // console.log("amtBnbLiquidity", amtBnbLiquidity);

        // 4. Add liquidity with remaining dino and re-bought busd and bnb
        IBEP20(busd).safeApprove(address(pancakeRouter), 0);
        IBEP20(busd).safeApprove(address(pancakeRouter), uint(-1));
        IBEP20(bnb).safeApprove(address(pancakeRouter), 0);
        IBEP20(bnb).safeApprove(address(pancakeRouter), uint(-1));

        (,,uint256 dinoBusdLpAmt) = pancakeRouter.addLiquidity(_dino,busd,amtDinoBought.div(4),amtBusdLiquidity,0,0,address(this),block.timestamp);
        (,,uint256 dinoBnbLpAmt) = pancakeRouter.addLiquidity(_dino,bnb,amtDinoBought.div(4),amtBnbLiquidity,0,0,address(this),block.timestamp);

        // 5. Burn LP tokens
        address dinoBusdPair = pancakeFactory.getPair(_dino, busd);
        address dinoBnbPair = pancakeFactory.getPair(_dino, bnb);

        IBEP20(dinoBusdPair).transfer(address(0x000000000000000000000000000000000000dEaD), dinoBusdLpAmt);
        IBEP20(dinoBnbPair).transfer(address(0x000000000000000000000000000000000000dEaD), dinoBnbLpAmt);
    }

    function _processDepositFeeSingleAsset(IBEP20 _stakingToken, uint256 _depositFee) internal {
        // console.log("single asset dump", _depositFee);
        address _dino = address(dino);

        // 1. Dump token to DINO
        _stakingToken.safeApprove(address(pancakeRouter), 0);
        _stakingToken.safeApprove(address(pancakeRouter), _depositFee);
        uint256 amtDinoBought = _swap(address(_stakingToken), _dino, _depositFee);
        // console.log("dino bought", amtDinoBought);

        // 3. Dump 1/4 DINO to BUSD and 1/4 to BNB to add to liquidity
        IBEP20(_dino).safeApprove(address(pancakeRouter), 0);
        IBEP20(_dino).safeApprove(address(pancakeRouter), uint(-1));
        uint256 amtBusdLiquidity = _swap(_dino, busd, amtDinoBought.div(4));
        uint256 amtBnbLiquidity = _swap(_dino, bnb, amtDinoBought.div(4));
        // console.log("amtBusdLiquidity", amtBusdLiquidity);
        // console.log("amtBnbLiquidity", amtBnbLiquidity);

        // 4. Add liquidity with remaining dino and re-bought busd and bnb
        IBEP20(busd).safeApprove(address(pancakeRouter), 0);
        IBEP20(busd).safeApprove(address(pancakeRouter), uint(-1));
        IBEP20(bnb).safeApprove(address(pancakeRouter), 0);
        IBEP20(bnb).safeApprove(address(pancakeRouter), uint(-1));

        (,,uint256 dinoBusdLpAmt) = pancakeRouter.addLiquidity(_dino,busd,amtDinoBought.div(4),amtBusdLiquidity,0,0,address(this),block.timestamp);
        (,,uint256 dinoBnbLpAmt) = pancakeRouter.addLiquidity(_dino,bnb,amtDinoBought.div(4),amtBnbLiquidity,0,0,address(this),block.timestamp);

        // 5. Burn LP tokens
        address dinoBusdPair = pancakeFactory.getPair(_dino, busd);
        address dinoBnbPair = pancakeFactory.getPair(_dino, bnb);

        IBEP20(dinoBusdPair).transfer(address(0x000000000000000000000000000000000000dEaD), dinoBusdLpAmt);
        IBEP20(dinoBnbPair).transfer(address(0x000000000000000000000000000000000000dEaD), dinoBnbLpAmt);
    }    
}

Changed text

Open file

/**
 *Submitted for verification at BscScan.com on 2021-02-21
*/

/**
 *Submitted for verification at BscScan.com on 2021-02-20
*/

pragma solidity 0.6.12;

// saltswap.finance

// 
/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        uint256 c = a + b;
        if (c < a) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b > a) return (false, 0);
        return (true, a - b);
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) return (true, 0);
        uint256 c = a * b;
        if (c / a != b) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a / b);
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a % b);
    }

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        return a - b;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: modulo by zero");
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        return a - b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a % b;
    }
}

interface IBEP20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the token decimals.
     */
    function decimals() external view returns (uint8);

    /**
     * @dev Returns the token symbol.
     */
    function symbol() external view returns (string memory);

    /**
     * @dev Returns the token name.
     */
    function name() external view returns (string memory);

    /**
     * @dev Returns the bep token owner.
     */
    function getOwner() external view returns (address);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address _owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

// 
/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain`call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
      return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: value }(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

// 
/**
 * @title SafeBEP20
 * @dev Wrappers around BEP20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeBEP20 for IBEP20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeBEP20 {
    using SafeMath for uint256;
    using Address for address;

    function safeTransfer(IBEP20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(IBEP20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IBEP20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(IBEP20 token, address spender, uint256 value) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        // solhint-disable-next-line max-line-length
        require((value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeBEP20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

    function safeIncreaseAllowance(IBEP20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).add(value);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    function safeDecreaseAllowance(IBEP20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeBEP20: decreased allowance below zero");
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IBEP20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.

        bytes memory returndata = address(token).functionCall(data, "SafeBEP20: low-level call failed");
        if (returndata.length > 0) { // Return data is optional
            // solhint-disable-next-line max-line-length
            require(abi.decode(returndata, (bool)), "SafeBEP20: BEP20 operation did not succeed");
        }
    }
}

// 
/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address payable) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

// 
/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor () internal {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

//

// 
/**
 * @dev Implementation of the {IBEP20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {BEP20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-BEP20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin guidelines: functions revert instead
 * of returning `false` on failure. This behavior is nonetheless conventional
 * and does not conflict with the expectations of BEP20 applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IBEP20-approve}.
 */
contract BEP20 is Context, IBEP20, Ownable {
    using SafeMath for uint256;

    mapping(address => uint256) private _balances;

    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;
    uint8 private _decimals;

    /**
     * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
     * a default value of 18.
     *
     * To select a different value for {decimals}, use {_setupDecimals}.
     *
     * All three of these values are immutable: they can only be set once during
     * construction.
     */
    constructor(string memory name, string memory symbol) public {
        _name = name;
        _symbol = symbol;
        _decimals = 18;
    }

    /**
     * @dev Returns the bep token owner.
     */
    function getOwner() external override view returns (address) {
        return owner();
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public override view returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public override view returns (string memory) {
        return _symbol;
    }

    /**
    * @dev Returns the number of decimals used to get its user representation.
    */
    function decimals() public override view returns (uint8) {
        return _decimals;
    }

    /**
     * @dev See {BEP20-totalSupply}.
     */
    function totalSupply() public override view returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {BEP20-balanceOf}.
     */
    function balanceOf(address account) public override view returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev See {BEP20-transfer}.
     *
     * Requirements:
     *
     * - `recipient` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address recipient, uint256 amount) public override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    /**
     * @dev See {BEP20-allowance}.
     */
    function allowance(address owner, address spender) public override view returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {BEP20-approve}.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }

    /**
     * @dev See {BEP20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {BEP20};
     *
     * Requirements:
     * - `sender` and `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     * - the caller must have allowance for `sender`'s tokens of at least
     * `amount`.
     */
    function transferFrom (address sender, address recipient, uint256 amount) public override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(
            sender,
            _msgSender(),
            _allowances[sender][_msgSender()].sub(amount, 'BEP20: transfer amount exceeds allowance')
        );
        return true;
    }

    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {BEP20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
        return true;
    }

    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {BEP20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, 'BEP20: decreased allowance below zero'));
        return true;
    }

    /**
     * @dev Creates `amount` tokens and assigns them to `msg.sender`, increasing
     * the total supply.
     *
     * Requirements
     *
     * - `msg.sender` must be the token owner
     */
    function mint(uint256 amount) public onlyOwner returns (bool) {
        _mint(_msgSender(), amount);
        return true;
    }

    /**
     * @dev Moves tokens `amount` from `sender` to `recipient`.
     *
     * This is internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `sender` cannot be the zero address.
     * - `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     */
    function _transfer (address sender, address recipient, uint256 amount) internal {
        require(sender != address(0), 'BEP20: transfer from the zero address');
        require(recipient != address(0), 'BEP20: transfer to the zero address');

        _balances[sender] = _balances[sender].sub(amount, 'BEP20: transfer amount exceeds balance');
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }

    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements
     *
     * - `to` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal {
        require(account != address(0), 'BEP20: mint to the zero address');

        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        emit Transfer(address(0), account, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal {
        require(account != address(0), 'BEP20: burn from the zero address');

        _balances[account] = _balances[account].sub(amount, 'BEP20: burn amount exceeds balance');
        _totalSupply = _totalSupply.sub(amount);
        emit Transfer(account, address(0), amount);
    }

    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner`s tokens.
     *
     * This is internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve (address owner, address spender, uint256 amount) internal {
        require(owner != address(0), 'BEP20: approve from the zero address');
        require(spender != address(0), 'BEP20: approve to the zero address');

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`.`amount` is then deducted
     * from the caller's allowance.
     *
     * See {_burn} and {_approve}.
     */
    function _burnFrom(address account, uint256 amount) internal {
        _burn(account, amount);
        _approve(account, _msgSender(), _allowances[account][_msgSender()].sub(amount, 'BEP20: burn amount exceeds allowance'));
    }
}

// SaltToken with Governance.
contract SaltToken is BEP20('Salt Token', 'SALT') {

    /// @notice Creates `_amount` token to `_to`. Must only be called by the owner (MasterChef).
    function mint(address _to, uint256 _amount) public onlyOwner {
        _mint(_to, _amount);
        _moveDelegates(address(0), _delegates[_to], _amount);
    }

    // Copied and modified from YAM code:
    // https://github.com/yam-finance/yam-protocol/blob/master/contracts/token/YAMGovernanceStorage.sol
    // https://github.com/yam-finance/yam-protocol/blob/master/contracts/token/YAMGovernance.sol
    // Which is copied and modified from COMPOUND:
    // https://github.com/compound-finance/compound-protocol/blob/master/contracts/Governance/Comp.sol

    /// @notice A record of each accounts delegate
    mapping (address => address) internal _delegates;

    /// @notice A checkpoint for marking number of votes from a given block
    struct Checkpoint {
        uint32 fromBlock;
        uint256 votes;
    }

    /// @notice A record of votes checkpoints for each account, by index
    mapping (address => mapping (uint32 => Checkpoint)) public checkpoints;

    /// @notice The number of checkpoints for each account
    mapping (address => uint32) public numCheckpoints;

    /// @notice The EIP-712 typehash for the contract's domain
    bytes32 public constant DOMAIN_TYPEHASH = keccak256("EIP712Domain(string name,uint256 chainId,address verifyingContract)");

    /// @notice The EIP-712 typehash for the delegation struct used by the contract
    bytes32 public constant DELEGATION_TYPEHASH = keccak256("Delegation(address delegatee,uint256 nonce,uint256 expiry)");

    /// @notice A record of states for signing / validating signatures
    mapping (address => uint) public nonces;

      /// @notice An event thats emitted when an account changes its delegate
    event DelegateChanged(address indexed delegator, address indexed fromDelegate, address indexed toDelegate);

    /// @notice An event thats emitted when a delegate account's vote balance changes
    event DelegateVotesChanged(address indexed delegate, uint previousBalance, uint newBalance);

    /**
     * @notice Delegate votes from `msg.sender` to `delegatee`
     * @param delegator The address to get delegatee for
     */
    function delegates(address delegator)
        external
        view
        returns (address)
    {
        return _delegates[delegator];
    }

   /**
    * @notice Delegate votes from `msg.sender` to `delegatee`
    * @param delegatee The address to delegate votes to
    */
    function delegate(address delegatee) external {
        return _delegate(msg.sender, delegatee);
    }

    /**
     * @notice Delegates votes from signatory to `delegatee`
     * @param delegatee The address to delegate votes to
     * @param nonce The contract state required to match the signature
     * @param expiry The time at which to expire the signature
     * @param v The recovery byte of the signature
     * @param r Half of the ECDSA signature pair
     * @param s Half of the ECDSA signature pair
     */
    function delegateBySig(
        address delegatee,
        uint nonce,
        uint expiry,
        uint8 v,
        bytes32 r,
        bytes32 s
    )
        external
    {
        bytes32 domainSeparator = keccak256(
            abi.encode(
                DOMAIN_TYPEHASH,
                keccak256(bytes(name())),
                getChainId(),
                address(this)
            )
        );

        bytes32 structHash = keccak256(
            abi.encode(
                DELEGATION_TYPEHASH,
                delegatee,
                nonce,
                expiry
            )
        );

        bytes32 digest = keccak256(
            abi.encodePacked(
                "\x19\x01",
                domainSeparator,
                structHash
            )
        );

        address signatory = ecrecover(digest, v, r, s);
        require(signatory != address(0), "SALT::delegateBySig: invalid signature");
        require(nonce == nonces[signatory]++, "SALT::delegateBySig: invalid nonce");
        require(now <= expiry, "SALT::delegateBySig: signature expired");
        return _delegate(signatory, delegatee);
    }

    /**
     * @notice Gets the current votes balance for `account`
     * @param account The address to get votes balance
     * @return The number of current votes for `account`
     */
    function getCurrentVotes(address account)
        external
        view
        returns (uint256)
    {
        uint32 nCheckpoints = numCheckpoints[account];
        return nCheckpoints > 0 ? checkpoints[account][nCheckpoints - 1].votes : 0;
    }

    /**
     * @notice Determine the prior number of votes for an account as of a block number
     * @dev Block number must be a finalized block or else this function will revert to prevent misinformation.
     * @param account The address of the account to check
     * @param blockNumber The block number to get the vote balance at
     * @return The number of votes the account had as of the given block
     */
    function getPriorVotes(address account, uint blockNumber)
        external
        view
        returns (uint256)
    {
        require(blockNumber < block.number, "SALT::getPriorVotes: not yet determined");

        uint32 nCheckpoints = numCheckpoints[account];
        if (nCheckpoints == 0) {
            return 0;
        }

        // First check most recent balance
        if (checkpoints[account][nCheckpoints - 1].fromBlock <= blockNumber) {
            return checkpoints[account][nCheckpoints - 1].votes;
        }

        // Next check implicit zero balance
        if (checkpoints[account][0].fromBlock > blockNumber) {
            return 0;
        }

        uint32 lower = 0;
        uint32 upper = nCheckpoints - 1;
        while (upper > lower) {
            uint32 center = upper - (upper - lower) / 2; // ceil, avoiding overflow
            Checkpoint memory cp = checkpoints[account][center];
            if (cp.fromBlock == blockNumber) {
                return cp.votes;
            } else if (cp.fromBlock < blockNumber) {
                lower = center;
            } else {
                upper = center - 1;
            }
        }
        return checkpoints[account][lower].votes;
    }

    function _delegate(address delegator, address delegatee)
        internal
    {
        address currentDelegate = _delegates[delegator];
        uint256 delegatorBalance = balanceOf(delegator); // balance of underlying SALTs (not scaled);
        _delegates[delegator] = delegatee;

        emit DelegateChanged(delegator, currentDelegate, delegatee);

        _moveDelegates(currentDelegate, delegatee, delegatorBalance);
    }

    function _moveDelegates(address srcRep, address dstRep, uint256 amount) internal {
        if (srcRep != dstRep && amount > 0) {
            if (srcRep != address(0)) {
                // decrease old representative
                uint32 srcRepNum = numCheckpoints[srcRep];
                uint256 srcRepOld = srcRepNum > 0 ? checkpoints[srcRep][srcRepNum - 1].votes : 0;
                uint256 srcRepNew = srcRepOld.sub(amount);
                _writeCheckpoint(srcRep, srcRepNum, srcRepOld, srcRepNew);
            }

            if (dstRep != address(0)) {
                // increase new representative
                uint32 dstRepNum = numCheckpoints[dstRep];
                uint256 dstRepOld = dstRepNum > 0 ? checkpoints[dstRep][dstRepNum - 1].votes : 0;
                uint256 dstRepNew = dstRepOld.add(amount);
                _writeCheckpoint(dstRep, dstRepNum, dstRepOld, dstRepNew);
            }
        }
    }

    function _writeCheckpoint(
        address delegatee,
        uint32 nCheckpoints,
        uint256 oldVotes,
        uint256 newVotes
    )
        internal
    {
        uint32 blockNumber = safe32(block.number, "SALT::_writeCheckpoint: block number exceeds 32 bits");

        if (nCheckpoints > 0 && checkpoints[delegatee][nCheckpoints - 1].fromBlock == blockNumber) {
            checkpoints[delegatee][nCheckpoints - 1].votes = newVotes;
        } else {
            checkpoints[delegatee][nCheckpoints] = Checkpoint(blockNumber, newVotes);
            numCheckpoints[delegatee] = nCheckpoints + 1;
        }

        emit DelegateVotesChanged(delegatee, oldVotes, newVotes);
    }

    function safe32(uint n, string memory errorMessage) internal pure returns (uint32) {
        require(n < 2**32, errorMessage);
        return uint32(n);
    }

    function getChainId() internal pure returns (uint) {
        uint256 chainId;
        assembly { chainId := chainid() }
        return chainId;
    }
}

// 
// MasterChef is the master of Salt. He can make Salt and he is a fair guy.
//
// Note that it's ownable and the owner wields tremendous power. The ownership
// will be transferred to a governance smart contract once SALT is sufficiently
// distributed and the community can show to govern itself.
//
// Have fun reading it. Hopefully it's bug-free. God bless.
contract MasterChef is Ownable {
    using SafeMath for uint256;
    using SafeBEP20 for IBEP20;

    // Info of each user.
    struct UserInfo {
        uint256 amount;         // How many LP tokens the user has provided.
        uint256 rewardDebt;     // Reward debt. See explanation below.
        //
        // We do some fancy math here. Basically, any point in time, the amount of SALTs
        // entitled to a user but is pending to be distributed is:
        //
        //   pending reward = (user.amount * pool.accSaltPerShare) - user.rewardDebt
        //
        // Whenever a user deposits or withdraws LP tokens to a pool. Here's what happens:
        //   1. The pool's `accSaltPerShare` (and `lastRewardBlock`) gets updated.
        //   2. User receives the pending reward sent to his/her address.
        //   3. User's `amount` gets updated.
        //   4. User's `rewardDebt` gets updated.
    }

    // Info of each pool.
    struct PoolInfo {
        IBEP20 lpToken;           // Address of LP token contract.
        uint256 allocPoint;       // How many allocation points assigned to this pool. SALTs to distribute per block.
        uint256 lastRewardBlock;  // Last block number that SALTs distribution occurs.
        uint256 accSaltPerShare;   // Accumulated SALTs per share, times 1e12. See below.
        uint16 depositFeeBP;      // Deposit fee in basis points
    }

    // The SALT TOKEN!
    SaltToken public salt;
    // Dev address.
    address public devaddr;
    // SALT tokens created per block.
    uint256 public saltPerBlock;
    // Bonus muliplier for early salt makers.
    uint256 public constant BONUS_MULTIPLIER = 1;
    // Deposit Fee address
    address public feeAddress;

    // Info of each pool.
    PoolInfo[] public poolInfo;
    // Info of each user that stakes LP tokens.
    mapping (uint256 => mapping (address => UserInfo)) public userInfo;
    // Total allocation points. Must be the sum of all allocation points in all pools.
    uint256 public totalAllocPoint = 0;
    // The block number when SALT mining starts.
    uint256 public startBlock;

    event Deposit(address indexed user, uint256 indexed pid, uint256 amount);
    event Withdraw(address indexed user, uint256 indexed pid, uint256 amount);
    event EmergencyWithdraw(address indexed user, uint256 indexed pid, uint256 amount);

    constructor(
        SaltToken _salt,
        address _devaddr,
        address _feeAddress,
        uint256 _saltPerBlock    
    ) public {
        salt = _salt;
        devaddr = _devaddr;
        feeAddress = _feeAddress;
        saltPerBlock = _saltPerBlock;
    }

    function poolLength() external view returns (uint256) {
        return poolInfo.length;
    }

    function setStartBlock(uint256 _startBlock) public onlyOwner {
        require(startBlock == 0, "already started");
        startBlock = _startBlock;
    }

    // Add a new lp to the pool. Can only be called by the owner.
    // XXX DO NOT add the same LP token more than once. Rewards will be messed up if you do.
    function add(uint256 _allocPoint, IBEP20 _lpToken, uint16 _depositFeeBP, bool _withUpdate) public onlyOwner {
        require(_depositFeeBP <= 10000, "add: invalid deposit fee basis points");
        if (_withUpdate) {
            massUpdatePools();
        }
        uint256 lastRewardBlock = block.number > startBlock ? block.number : startBlock;
        totalAllocPoint = totalAllocPoint.add(_allocPoint);
        poolInfo.push(PoolInfo({
            lpToken: _lpToken,
            allocPoint: _allocPoint,
            lastRewardBlock: lastRewardBlock,
            accSaltPerShare: 0,
            depositFeeBP: _depositFeeBP
        }));
    }

    // Update the given pool's SALT allocation point and deposit fee. Can only be called by the owner.
    function set(uint256 _pid, uint256 _allocPoint, uint16 _depositFeeBP, bool _withUpdate) public onlyOwner {
        require(_depositFeeBP <= 10000, "set: invalid deposit fee basis points");
        if (_withUpdate) {
            massUpdatePools();
        }
        totalAllocPoint = totalAllocPoint.sub(poolInfo[_pid].allocPoint).add(_allocPoint);
        poolInfo[_pid].allocPoint = _allocPoint;
        poolInfo[_pid].depositFeeBP = _depositFeeBP;
    }

    // Return reward multiplier over the given _from to _to block.
    function getMultiplier(uint256 _from, uint256 _to) public view returns (uint256) {
        return _to.sub(_from).mul(BONUS_MULTIPLIER);
    }

    // View function to see pending SALTs on frontend.
    function pendingSalt(uint256 _pid, address _user) external view returns (uint256) {
        PoolInfo storage pool = poolInfo[_pid];
        UserInfo storage user = userInfo[_pid][_user];
        uint256 accSaltPerShare = pool.accSaltPerShare;
        uint256 lpSupply = pool.lpToken.balanceOf(address(this));
        if (block.number > pool.lastRewardBlock && lpSupply != 0) {
            uint256 multiplier = getMultiplier(pool.lastRewardBlock, block.number);
            uint256 saltReward = multiplier.mul(saltPerBlock).mul(pool.allocPoint).div(totalAllocPoint);
            accSaltPerShare = accSaltPerShare.add(saltReward.mul(1e12).div(lpSupply));
        }
        return user.amount.mul(accSaltPerShare).div(1e12).sub(user.rewardDebt);
    }

    // Update reward variables for all pools. Be careful of gas spending!
    function massUpdatePools() public {
        uint256 length = poolInfo.length;
        for (uint256 pid = 0; pid < length; ++pid) {
            updatePool(pid);
        }
    }

    // Update reward variables of the given pool to be up-to-date.
    function updatePool(uint256 _pid) public {
        PoolInfo storage pool = poolInfo[_pid];
        if (block.number <= pool.lastRewardBlock) {
            return;
        }
        uint256 lpSupply = pool.lpToken.balanceOf(address(this));
        if (lpSupply == 0 || pool.allocPoint == 0) {
            pool.lastRewardBlock = block.number;
            return;
        }
        uint256 multiplier = getMultiplier(pool.lastRewardBlock, block.number);
        uint256 saltReward = multiplier.mul(saltPerBlock).mul(pool.allocPoint).div(totalAllocPoint);
        salt.mint(devaddr, saltReward.div(10));
        salt.mint(address(this), saltReward);
        pool.accSaltPerShare = pool.accSaltPerShare.add(saltReward.mul(1e12).div(lpSupply));
        pool.lastRewardBlock = block.number;
    }

    // Deposit LP tokens to MasterChef for SALT allocation.
    function deposit(uint256 _pid, uint256 _amount) public {
        PoolInfo storage pool = poolInfo[_pid];
        UserInfo storage user = userInfo[_pid][msg.sender];
        updatePool(_pid);
        if (user.amount > 0) {
            uint256 pending = user.amount.mul(pool.accSaltPerShare).div(1e12).sub(user.rewardDebt);
            if(pending > 0) {
                safeSaltTransfer(msg.sender, pending);
            }
        }
        if(_amount > 0) {
            pool.lpToken.safeTransferFrom(address(msg.sender), address(this), _amount);
            if(pool.depositFeeBP > 0){
                uint256 depositFee = _amount.mul(pool.depositFeeBP).div(10000);
                pool.lpToken.safeTransfer(feeAddress, depositFee);
                user.amount = user.amount.add(_amount).sub(depositFee);
            }else{
                user.amount = user.amount.add(_amount);
            }
        }
        user.rewardDebt = user.amount.mul(pool.accSaltPerShare).div(1e12);
        emit Deposit(msg.sender, _pid, _amount);
    }

    // Withdraw LP tokens from MasterChef.
    function withdraw(uint256 _pid, uint256 _amount) public {
        PoolInfo storage pool = poolInfo[_pid];
        UserInfo storage user = userInfo[_pid][msg.sender];
        require(user.amount >= _amount, "withdraw: not good");
        updatePool(_pid);
        uint256 pending = user.amount.mul(pool.accSaltPerShare).div(1e12).sub(user.rewardDebt);
        if(pending > 0) {
            safeSaltTransfer(msg.sender, pending);
        }
        if(_amount > 0) {
            user.amount = user.amount.sub(_amount);
            pool.lpToken.safeTransfer(address(msg.sender), _amount);
        }
        user.rewardDebt = user.amount.mul(pool.accSaltPerShare).div(1e12);
        emit Withdraw(msg.sender, _pid, _amount);
    }

    // Withdraw without caring about rewards. EMERGENCY ONLY.
    function emergencyWithdraw(uint256 _pid) public {
        PoolInfo storage pool = poolInfo[_pid];
        UserInfo storage user = userInfo[_pid][msg.sender];
        uint256 amount = user.amount;
        user.amount = 0;
        user.rewardDebt = 0;
        pool.lpToken.safeTransfer(address(msg.sender), amount);
        emit EmergencyWithdraw(msg.sender, _pid, amount);
    }

    // Safe salt transfer function, just in case if rounding error causes pool to not have enough SALTs.
    function safeSaltTransfer(address _to, uint256 _amount) internal {
        uint256 saltBal = salt.balanceOf(address(this));
        if (_amount > saltBal) {
            salt.transfer(_to, saltBal);
        } else {
            salt.transfer(_to, _amount);
        }
    }

    // Update dev address by the previous dev.
    function dev(address _devaddr) public {
        require(msg.sender == devaddr, "dev: wut?");
        devaddr = _devaddr;
    }

    function setFeeAddress(address _feeAddress) public{
        require(msg.sender == feeAddress, "setFeeAddress: FORBIDDEN");
        feeAddress = _feeAddress;
    }

    //Pancake has to add hidden dummy pools inorder to alter the emission, here we make it simple and transparent to all.
    function updateEmissionRate(uint256 _saltPerBlock) public onlyOwner {
        massUpdatePools();
        saltPerBlock = _saltPerBlock;
    }
}