// This contract is part of Zellic’s smart contract dataset, which is a collection of publicly available contract code gathered as of March 2023. | |
// SPDX-License-Identifier: Unlicensed | |
pragma solidity 0.8.15; | |
/** | |
* @dev Interface of the ERC20 standard as defined in the EIP. | |
*/ | |
interface IERC20 { | |
/** | |
* @dev Returns the amount of tokens in existence. | |
*/ | |
function totalSupply() external view returns (uint256); | |
/** | |
* @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 Interface for the optional metadata functions from the ERC20 standard. | |
* | |
* _Available since v4.1._ | |
*/ | |
interface IERC20Metadata is IERC20 { | |
/** | |
* @dev Returns the name of the token. | |
*/ | |
function name() external view returns (string memory); | |
/** | |
* @dev Returns the symbol of the token. | |
*/ | |
function symbol() external view returns (string memory); | |
/** | |
* @dev Returns the decimals places of the token. | |
*/ | |
function decimals() external view returns (uint8); | |
} | |
abstract contract Context { | |
function _msgSender() internal view virtual returns (address) { | |
return msg.sender; | |
} | |
function _msgData() internal view virtual returns (bytes calldata) { | |
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() { | |
_setOwner(address(0)); | |
} | |
/** | |
* @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"); | |
_; | |
} | |
function _setOwner(address newOwner) private { | |
address oldOwner = _owner; | |
_owner = newOwner; | |
emit OwnershipTransferred(oldOwner, newOwner); | |
} | |
} | |
/** | |
* @dev Implementation of the {IERC20} 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 create supply function. | |
* For a generic mechanism see {ERC20PresetMinterPauser}. | |
* | |
* TIP: For a detailed writeup see our guide | |
* https://forum.zeppelin.solutions/t/how-to-implement-erc20-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 ERC20 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 {IERC20-approve}. | |
*/ | |
contract ERC20 is Context, IERC20, IERC20Metadata { | |
mapping(address => uint256) private _balances; | |
mapping(address => mapping(address => uint256)) private _allowances; | |
uint256 private _totalSupply; | |
string private _name; | |
string private _symbol; | |
/** | |
* @dev Sets the values for {name} and {symbol}. | |
* | |
* The default value of {decimals} is 18. To select a different value for | |
* {decimals} you should overload it. | |
* | |
* All two of these values are immutable: they can only be set once during | |
* construction. | |
*/ | |
constructor(string memory name_, string memory symbol_) { | |
_name = name_; | |
_symbol = symbol_; | |
} | |
/** | |
* @dev Returns the name of the token. | |
*/ | |
function name() public view virtual override returns (string memory) { | |
return _name; | |
} | |
/** | |
* @dev Returns the symbol of the token, usually a shorter version of the | |
* name. | |
*/ | |
function symbol() public view virtual override returns (string memory) { | |
return _symbol; | |
} | |
/** | |
* @dev Returns the number of decimals used to get its user representation. | |
* For example, if `decimals` equals `2`, a balance of `505` tokens should | |
* be displayed to a user as `5,05` (`505 / 10 ** 2`). | |
* | |
* Tokens usually opt for a value of 18, imitating the relationship between | |
* Ether and Wei. This is the value {ERC20} uses, unless this function is | |
* overridden; | |
* | |
* NOTE: This information is only used for _display_ purposes: it in | |
* no way affects any of the arithmetic of the contract, including | |
* {IERC20-balanceOf} and {IERC20-transfer}. | |
*/ | |
function decimals() public view virtual override returns (uint8) { | |
return 18; | |
} | |
/** | |
* @dev See {IERC20-totalSupply}. | |
*/ | |
function totalSupply() public view virtual override returns (uint256) { | |
return _totalSupply; | |
} | |
/** | |
* @dev See {IERC20-balanceOf}. | |
*/ | |
function balanceOf(address account) public view virtual override returns (uint256) { | |
return _balances[account]; | |
} | |
/** | |
* @dev See {IERC20-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 virtual override returns (bool) { | |
_transfer(_msgSender(), recipient, amount); | |
return true; | |
} | |
/** | |
* @dev See {IERC20-allowance}. | |
*/ | |
function allowance(address owner, address spender) public view virtual override returns (uint256) { | |
return _allowances[owner][spender]; | |
} | |
/** | |
* @dev See {IERC20-approve}. | |
* | |
* Requirements: | |
* | |
* - `spender` cannot be the zero address. | |
*/ | |
function approve(address spender, uint256 amount) public virtual override returns (bool) { | |
_approve(_msgSender(), spender, amount); | |
return true; | |
} | |
/** | |
* @dev See {IERC20-transferFrom}. | |
* | |
* Emits an {Approval} event indicating the updated allowance. This is not | |
* required by the EIP. See the note at the beginning of {ERC20}. | |
* | |
* 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 virtual override returns (bool) { | |
_transfer(sender, recipient, amount); | |
uint256 currentAllowance = _allowances[sender][_msgSender()]; | |
require(currentAllowance >= amount, "ERC20: transfer amount exceeds allowance"); | |
unchecked { | |
_approve(sender, _msgSender(), currentAllowance - amount); | |
} | |
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 {IERC20-approve}. | |
* | |
* Emits an {Approval} event indicating the updated allowance. | |
* | |
* Requirements: | |
* | |
* - `spender` cannot be the zero address. | |
*/ | |
function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) { | |
_approve(_msgSender(), spender, _allowances[_msgSender()][spender] + 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 {IERC20-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 virtual returns (bool) { | |
uint256 currentAllowance = _allowances[_msgSender()][spender]; | |
require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero"); | |
unchecked { | |
_approve(_msgSender(), spender, currentAllowance - subtractedValue); | |
} | |
return true; | |
} | |
/** | |
* @dev Moves `amount` of tokens from `sender` to `recipient`. | |
* | |
* This 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 virtual { | |
require(sender != address(0), "ERC20: transfer from the zero address"); | |
require(recipient != address(0), "ERC20: transfer to the zero address"); | |
_beforeTokenTransfer(sender, recipient, amount); | |
uint256 senderBalance = _balances[sender]; | |
require(senderBalance >= amount, "ERC20: transfer amount exceeds balance"); | |
unchecked { | |
_balances[sender] = senderBalance - amount; | |
} | |
_balances[recipient] += amount; | |
emit Transfer(sender, recipient, amount); | |
_afterTokenTransfer(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: | |
* | |
* - `account` cannot be the zero address. | |
*/ | |
function _createSupply(address account, uint256 amount) internal virtual { | |
require(account != address(0), "ERC20: mint to the zero address"); | |
_beforeTokenTransfer(address(0), account, amount); | |
_totalSupply += amount; | |
_balances[account] += amount; | |
emit Transfer(address(0), account, amount); | |
_afterTokenTransfer(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 virtual { | |
require(account != address(0), "ERC20: burn from the zero address"); | |
_beforeTokenTransfer(account, address(0), amount); | |
uint256 accountBalance = _balances[account]; | |
require(accountBalance >= amount, "ERC20: burn amount exceeds balance"); | |
unchecked { | |
_balances[account] = accountBalance - amount; | |
} | |
_totalSupply -= amount; | |
emit Transfer(account, address(0), amount); | |
_afterTokenTransfer(account, address(0), amount); | |
} | |
/** | |
* @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens. | |
* | |
* This 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 virtual { | |
require(owner != address(0), "ERC20: approve from the zero address"); | |
require(spender != address(0), "ERC20: approve to the zero address"); | |
_allowances[owner][spender] = amount; | |
emit Approval(owner, spender, amount); | |
} | |
/** | |
* @dev Hook that is called before any transfer of tokens. This includes | |
* minting and burning. | |
* | |
* Calling conditions: | |
* | |
* - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens | |
* will be transferred to `to`. | |
* - when `from` is zero, `amount` tokens will be minted for `to`. | |
* - when `to` is zero, `amount` of ``from``'s tokens will be burned. | |
* - `from` and `to` are never both zero. | |
* | |
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks]. | |
*/ | |
function _beforeTokenTransfer( | |
address from, | |
address to, | |
uint256 amount | |
) internal virtual {} | |
/** | |
* @dev Hook that is called after any transfer of tokens. This includes | |
* minting and burning. | |
* | |
* Calling conditions: | |
* | |
* - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens | |
* has been transferred to `to`. | |
* - when `from` is zero, `amount` tokens have been minted for `to`. | |
* - when `to` is zero, `amount` of ``from``'s tokens have been burned. | |
* - `from` and `to` are never both zero. | |
* | |
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks]. | |
*/ | |
function _afterTokenTransfer( | |
address from, | |
address to, | |
uint256 amount | |
) internal virtual {} | |
} | |
interface IUniswapV2Router01 { | |
function factory() external pure returns (address); | |
function WETH() external pure returns (address); | |
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 addLiquidityETH( | |
address token, | |
uint amountTokenDesired, | |
uint amountTokenMin, | |
uint amountETHMin, | |
address to, | |
uint deadline | |
) external payable returns (uint amountToken, uint amountETH, uint liquidity); | |
function removeLiquidity( | |
address tokenA, | |
address tokenB, | |
uint liquidity, | |
uint amountAMin, | |
uint amountBMin, | |
address to, | |
uint deadline | |
) external returns (uint amountA, uint amountB); | |
function removeLiquidityETH( | |
address token, | |
uint liquidity, | |
uint amountTokenMin, | |
uint amountETHMin, | |
address to, | |
uint deadline | |
) external returns (uint amountToken, uint amountETH); | |
function removeLiquidityWithPermit( | |
address tokenA, | |
address tokenB, | |
uint liquidity, | |
uint amountAMin, | |
uint amountBMin, | |
address to, | |
uint deadline, | |
bool approveMax, uint8 v, bytes32 r, bytes32 s | |
) external returns (uint amountA, uint amountB); | |
function removeLiquidityETHWithPermit( | |
address token, | |
uint liquidity, | |
uint amountTokenMin, | |
uint amountETHMin, | |
address to, | |
uint deadline, | |
bool approveMax, uint8 v, bytes32 r, bytes32 s | |
) external returns (uint amountToken, uint amountETH); | |
function swapExactTokensForTokens( | |
uint amountIn, | |
uint amountOutMin, | |
address[] calldata path, | |
address to, | |
uint deadline | |
) external returns (uint[] memory amounts); | |
function swapTokensForExactTokens( | |
uint amountOut, | |
uint amountInMax, | |
address[] calldata path, | |
address to, | |
uint deadline | |
) external returns (uint[] memory amounts); | |
function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline) | |
external | |
payable | |
returns (uint[] memory amounts); | |
function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline) | |
external | |
returns (uint[] memory amounts); | |
function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline) | |
external | |
returns (uint[] memory amounts); | |
function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline) | |
external | |
payable | |
returns (uint[] memory amounts); | |
function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB); | |
function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut); | |
function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn); | |
function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts); | |
function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts); | |
} | |
interface IUniswapV2Router02 is IUniswapV2Router01 { | |
function removeLiquidityETHSupportingFeeOnTransferTokens( | |
address token, | |
uint liquidity, | |
uint amountTokenMin, | |
uint amountETHMin, | |
address to, | |
uint deadline | |
) external returns (uint amountETH); | |
function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens( | |
address token, | |
uint liquidity, | |
uint amountTokenMin, | |
uint amountETHMin, | |
address to, | |
uint deadline, | |
bool approveMax, uint8 v, bytes32 r, bytes32 s | |
) external returns (uint amountETH); | |
function swapExactTokensForTokensSupportingFeeOnTransferTokens( | |
uint amountIn, | |
uint amountOutMin, | |
address[] calldata path, | |
address to, | |
uint deadline | |
) external; | |
function swapExactETHForTokensSupportingFeeOnTransferTokens( | |
uint amountOutMin, | |
address[] calldata path, | |
address to, | |
uint deadline | |
) external payable; | |
function swapExactTokensForETHSupportingFeeOnTransferTokens( | |
uint amountIn, | |
uint amountOutMin, | |
address[] calldata path, | |
address to, | |
uint deadline | |
) external; | |
} | |
interface IUniswapV2Factory { | |
event PairCreated(address indexed token0, address indexed token1, address pair, uint); | |
function feeTo() external view returns (address); | |
function feeToSetter() external view returns (address); | |
function getPair(address tokenA, address tokenB) external view returns (address pair); | |
function allPairs(uint) external view returns (address pair); | |
function allPairsLength() external view returns (uint); | |
function createPair(address tokenA, address tokenB) external returns (address pair); | |
function setFeeTo(address) external; | |
function setFeeToSetter(address) external; | |
} | |
/** | |
* @dev Wrappers over Solidity's arithmetic operations. | |
* | |
* NOTE: `SignedSafeMath` is no longer needed starting with Solidity 0.8. The compiler | |
* now has built in overflow checking. | |
*/ | |
library SignedSafeMath { | |
/** | |
* @dev Returns the multiplication of two signed integers, reverting on | |
* overflow. | |
* | |
* Counterpart to Solidity's `*` operator. | |
* | |
* Requirements: | |
* | |
* - Multiplication cannot overflow. | |
*/ | |
function mul(int256 a, int256 b) internal pure returns (int256) { | |
return a * b; | |
} | |
/** | |
* @dev Returns the integer division of two signed integers. Reverts on | |
* division by zero. The result is rounded towards zero. | |
* | |
* Counterpart to Solidity's `/` operator. | |
* | |
* Requirements: | |
* | |
* - The divisor cannot be zero. | |
*/ | |
function div(int256 a, int256 b) internal pure returns (int256) { | |
return a / b; | |
} | |
/** | |
* @dev Returns the subtraction of two signed integers, reverting on | |
* overflow. | |
* | |
* Counterpart to Solidity's `-` operator. | |
* | |
* Requirements: | |
* | |
* - Subtraction cannot overflow. | |
*/ | |
function sub(int256 a, int256 b) internal pure returns (int256) { | |
return a - b; | |
} | |
/** | |
* @dev Returns the addition of two signed integers, reverting on | |
* overflow. | |
* | |
* Counterpart to Solidity's `+` operator. | |
* | |
* Requirements: | |
* | |
* - Addition cannot overflow. | |
*/ | |
function add(int256 a, int256 b) internal pure returns (int256) { | |
return a + b; | |
} | |
} | |
// CAUTION | |
// This version of SafeMath should only be used with Solidity 0.8 or later, | |
// because it relies on the compiler's built in overflow checks. | |
/** | |
* @dev Wrappers over Solidity's arithmetic operations. | |
* | |
* NOTE: `SafeMath` is no longer needed starting with Solidity 0.8. The compiler | |
* now has built in overflow checking. | |
*/ | |
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) { | |
unchecked { | |
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) { | |
unchecked { | |
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) { | |
unchecked { | |
// 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) { | |
unchecked { | |
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) { | |
unchecked { | |
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) { | |
return a + b; | |
} | |
/** | |
* @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 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) { | |
return a * b; | |
} | |
/** | |
* @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. | |
* | |
* Requirements: | |
* | |
* - The divisor cannot be zero. | |
*/ | |
function div(uint256 a, uint256 b) internal pure returns (uint256) { | |
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) { | |
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) { | |
unchecked { | |
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. | |
* | |
* 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) { | |
unchecked { | |
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) { | |
unchecked { | |
require(b > 0, errorMessage); | |
return a % b; | |
} | |
} | |
} | |
/** | |
* @dev Wrappers over Solidity's uintXX/intXX casting operators with added overflow | |
* checks. | |
* | |
* Downcasting from uint256/int256 in Solidity does not revert on overflow. This can | |
* easily result in undesired exploitation or bugs, since developers usually | |
* assume that overflows raise errors. `SafeCast` restores this intuition by | |
* reverting the transaction when such 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. | |
* | |
* Can be combined with {SafeMath} and {SignedSafeMath} to extend it to smaller types, by performing | |
* all math on `uint256` and `int256` and then downcasting. | |
*/ | |
library SafeCast { | |
/** | |
* @dev Returns the downcasted uint224 from uint256, reverting on | |
* overflow (when the input is greater than largest uint224). | |
* | |
* Counterpart to Solidity's `uint224` operator. | |
* | |
* Requirements: | |
* | |
* - input must fit into 224 bits | |
*/ | |
function toUint224(uint256 value) internal pure returns (uint224) { | |
require(value <= type(uint224).max, "SafeCast: value doesn't fit in 224 bits"); | |
return uint224(value); | |
} | |
/** | |
* @dev Returns the downcasted uint128 from uint256, reverting on | |
* overflow (when the input is greater than largest uint128). | |
* | |
* Counterpart to Solidity's `uint128` operator. | |
* | |
* Requirements: | |
* | |
* - input must fit into 128 bits | |
*/ | |
function toUint128(uint256 value) internal pure returns (uint128) { | |
require(value <= type(uint128).max, "SafeCast: value doesn't fit in 128 bits"); | |
return uint128(value); | |
} | |
/** | |
* @dev Returns the downcasted uint96 from uint256, reverting on | |
* overflow (when the input is greater than largest uint96). | |
* | |
* Counterpart to Solidity's `uint96` operator. | |
* | |
* Requirements: | |
* | |
* - input must fit into 96 bits | |
*/ | |
function toUint96(uint256 value) internal pure returns (uint96) { | |
require(value <= type(uint96).max, "SafeCast: value doesn't fit in 96 bits"); | |
return uint96(value); | |
} | |
/** | |
* @dev Returns the downcasted uint64 from uint256, reverting on | |
* overflow (when the input is greater than largest uint64). | |
* | |
* Counterpart to Solidity's `uint64` operator. | |
* | |
* Requirements: | |
* | |
* - input must fit into 64 bits | |
*/ | |
function toUint64(uint256 value) internal pure returns (uint64) { | |
require(value <= type(uint64).max, "SafeCast: value doesn't fit in 64 bits"); | |
return uint64(value); | |
} | |
/** | |
* @dev Returns the downcasted uint32 from uint256, reverting on | |
* overflow (when the input is greater than largest uint32). | |
* | |
* Counterpart to Solidity's `uint32` operator. | |
* | |
* Requirements: | |
* | |
* - input must fit into 32 bits | |
*/ | |
function toUint32(uint256 value) internal pure returns (uint32) { | |
require(value <= type(uint32).max, "SafeCast: value doesn't fit in 32 bits"); | |
return uint32(value); | |
} | |
/** | |
* @dev Returns the downcasted uint16 from uint256, reverting on | |
* overflow (when the input is greater than largest uint16). | |
* | |
* Counterpart to Solidity's `uint16` operator. | |
* | |
* Requirements: | |
* | |
* - input must fit into 16 bits | |
*/ | |
function toUint16(uint256 value) internal pure returns (uint16) { | |
require(value <= type(uint16).max, "SafeCast: value doesn't fit in 16 bits"); | |
return uint16(value); | |
} | |
/** | |
* @dev Returns the downcasted uint8 from uint256, reverting on | |
* overflow (when the input is greater than largest uint8). | |
* | |
* Counterpart to Solidity's `uint8` operator. | |
* | |
* Requirements: | |
* | |
* - input must fit into 8 bits. | |
*/ | |
function toUint8(uint256 value) internal pure returns (uint8) { | |
require(value <= type(uint8).max, "SafeCast: value doesn't fit in 8 bits"); | |
return uint8(value); | |
} | |
/** | |
* @dev Converts a signed int256 into an unsigned uint256. | |
* | |
* Requirements: | |
* | |
* - input must be greater than or equal to 0. | |
*/ | |
function toUint256(int256 value) internal pure returns (uint256) { | |
require(value >= 0, "SafeCast: value must be positive"); | |
return uint256(value); | |
} | |
/** | |
* @dev Returns the downcasted int128 from int256, reverting on | |
* overflow (when the input is less than smallest int128 or | |
* greater than largest int128). | |
* | |
* Counterpart to Solidity's `int128` operator. | |
* | |
* Requirements: | |
* | |
* - input must fit into 128 bits | |
* | |
* _Available since v3.1._ | |
*/ | |
function toInt128(int256 value) internal pure returns (int128) { | |
require(value >= type(int128).min && value <= type(int128).max, "SafeCast: value doesn't fit in 128 bits"); | |
return int128(value); | |
} | |
/** | |
* @dev Returns the downcasted int64 from int256, reverting on | |
* overflow (when the input is less than smallest int64 or | |
* greater than largest int64). | |
* | |
* Counterpart to Solidity's `int64` operator. | |
* | |
* Requirements: | |
* | |
* - input must fit into 64 bits | |
* | |
* _Available since v3.1._ | |
*/ | |
function toInt64(int256 value) internal pure returns (int64) { | |
require(value >= type(int64).min && value <= type(int64).max, "SafeCast: value doesn't fit in 64 bits"); | |
return int64(value); | |
} | |
/** | |
* @dev Returns the downcasted int32 from int256, reverting on | |
* overflow (when the input is less than smallest int32 or | |
* greater than largest int32). | |
* | |
* Counterpart to Solidity's `int32` operator. | |
* | |
* Requirements: | |
* | |
* - input must fit into 32 bits | |
* | |
* _Available since v3.1._ | |
*/ | |
function toInt32(int256 value) internal pure returns (int32) { | |
require(value >= type(int32).min && value <= type(int32).max, "SafeCast: value doesn't fit in 32 bits"); | |
return int32(value); | |
} | |
/** | |
* @dev Returns the downcasted int16 from int256, reverting on | |
* overflow (when the input is less than smallest int16 or | |
* greater than largest int16). | |
* | |
* Counterpart to Solidity's `int16` operator. | |
* | |
* Requirements: | |
* | |
* - input must fit into 16 bits | |
* | |
* _Available since v3.1._ | |
*/ | |
function toInt16(int256 value) internal pure returns (int16) { | |
require(value >= type(int16).min && value <= type(int16).max, "SafeCast: value doesn't fit in 16 bits"); | |
return int16(value); | |
} | |
/** | |
* @dev Returns the downcasted int8 from int256, reverting on | |
* overflow (when the input is less than smallest int8 or | |
* greater than largest int8). | |
* | |
* Counterpart to Solidity's `int8` operator. | |
* | |
* Requirements: | |
* | |
* - input must fit into 8 bits. | |
* | |
* _Available since v3.1._ | |
*/ | |
function toInt8(int256 value) internal pure returns (int8) { | |
require(value >= type(int8).min && value <= type(int8).max, "SafeCast: value doesn't fit in 8 bits"); | |
return int8(value); | |
} | |
/** | |
* @dev Converts an unsigned uint256 into a signed int256. | |
* | |
* Requirements: | |
* | |
* - input must be less than or equal to maxInt256. | |
*/ | |
function toInt256(uint256 value) internal pure returns (int256) { | |
// Note: Unsafe cast below is okay because `type(int256).max` is guaranteed to be positive | |
require(value <= uint256(type(int256).max), "SafeCast: value doesn't fit in an int256"); | |
return int256(value); | |
} | |
} | |
contract Supercats is ERC20, Ownable { | |
using SafeMath for uint256; | |
IUniswapV2Router02 private uniswapV2Router; | |
address private immutable uniswapV2Pair; | |
uint256 public marketingFee = 3; | |
uint256 public maxWalletToken = 2000000 * 10**18; | |
address public marketingWallet = 0x8c84fB2D99Ca548a145aD4ef60b7F39Df1EaadB1; | |
// exlcude from fees and max wallet limit | |
mapping (address => bool) private _isExcludedFromFees; | |
constructor() ERC20("Supercats", "$CT$") { | |
IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D); | |
// Create a uniswap pair for this new token | |
address _uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory()) | |
.createPair(address(this), _uniswapV2Router.WETH()); | |
uniswapV2Router = _uniswapV2Router; | |
uniswapV2Pair = _uniswapV2Pair; | |
// exclude from paying fees or max wallet limit | |
_isExcludedFromFees[_msgSender()] = true; | |
_isExcludedFromFees[marketingWallet] = true; | |
/* | |
an internal function in ERC20.sol that is only called here, | |
and CANNOT be called ever again | |
*/ | |
_createSupply(_msgSender(), 100000000 * (10**18)); | |
} | |
function _transfer( | |
address from, | |
address to, | |
uint256 amount | |
) internal override { | |
require(from != address(0), "ERC20: transfer from the zero address"); | |
require(to != address(0), "ERC20: transfer to the zero address"); | |
if(amount == 0) { | |
super._transfer(from, to, 0); | |
return; | |
} | |
bool excludedAccount = _isExcludedFromFees[from] || _isExcludedFromFees[to]; | |
if (from == uniswapV2Pair && !excludedAccount) { | |
uint256 contractBalanceRecepient = balanceOf(to); | |
require(contractBalanceRecepient + amount <= maxWalletToken,"Exceeds maximum wallet token amount."); | |
} | |
// if any account belongs to _isExcludedFromFee account then remove the fee | |
if(!excludedAccount && (from == uniswapV2Pair || to == uniswapV2Pair)) { | |
uint256 fees = amount.mul(marketingFee).div(100); | |
super._transfer(from, marketingWallet, fees); | |
amount = amount.sub(fees); | |
} | |
super._transfer(from, to, amount); | |
} | |
} |