File 1 of 1: yapper.sol
pragma solidity 0.8.22;
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
}
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
);
}
library SafeMath {
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
return sub(a, b, "SafeMath: 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, "SafeMath: multiplication overflow");
return c;
}
function div(uint256 a, uint256 b) internal pure returns (uint256) {
return div(a, b, "SafeMath: 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(), "Ownable: caller is not the owner");
_;
}
function renounceOwnership() public virtual onlyOwner {
emit OwnershipTransferred(_owner, address(0));
_owner = address(0);
}
}
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);
function addLiquidityETH(
address token,
uint256 amountTokenDesired,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline
)
external
payable
returns (
uint256 amountToken,
uint256 amountETH,
uint256 liquidity
);
}
contract yapper is Context, IERC20, Ownable {
using SafeMath for uint256;
mapping(address => uint256) private _balances;
mapping(address => mapping(address => uint256)) private _allowances;
mapping(address => bool) private _isExcludedFromFee;
mapping(address => bool) private bots;
address payable private _taxWallet;
uint256 firstBlock;
uint256 private _initialBuyTax = 22;
uint256 private _initialSellTax = 22;
uint256 private _finalBuyTax = 0;
uint256 private _finalSellTax = 0;
uint256 private _reduceBuyTaxAt = 5;
uint256 private _reduceSellTaxAt = 5;
uint256 private _preventSwapBefore = 5;
uint256 private _buyCount = 0;
uint8 private constant _decimals = 9;
uint256 private constant _tTotal = 1000000000 * 10**_decimals;
string private constant _name = unicode"Yapper";
string private constant _symbol = unicode"YAP";
uint256 public _maxTxAmount = 20000000 * 10**_decimals;
uint256 public _maxWalletSize = 20000000 * 10**_decimals;
uint256 public _taxSwapThreshold = 20000000 * 10**_decimals;
uint256 public _maxTaxSwap = 20000000 * 10**_decimals;
IUniswapV2Router02 private uniswapV2Router;
address private uniswapV2Pair;
bool private tradingOpen;
bool private inSwap = false;
bool private swapEnabled = false;
event MaxTxAmountUpdated(uint256 _maxTxAmount);
modifier lockTheSwap() {
inSwap = true;
_;
inSwap = false;
}
constructor() {
_taxWallet = payable(_msgSender());
_balances[_msgSender()] = _tTotal;
_isExcludedFromFee[owner()] = true;
_isExcludedFromFee[address(this)] = true;
_isExcludedFromFee[_taxWallet] = true;
emit Transfer(address(0), _msgSender(), _tTotal);
}
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 _tTotal;
}
function balanceOf(address account) public view override returns (uint256) {
return _balances[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 transferFrom(
address sender,
address recipient,
uint256 amount
) public override returns (bool) {
_transfer(sender, recipient, amount);
_approve(
sender,
_msgSender(),
_allowances[sender][_msgSender()].sub(
amount,
"ERC20: transfer amount exceeds allowance"
)
);
return true;
}
function _approve(
address owner,
address spender,
uint256 amount
) private {
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);
}
function _transfer(
address from,
address to,
uint256 amount
) private {
require(from != address(0), "ERC20: transfer from the zero address");
require(to != address(0), "ERC20: transfer to the zero address");
require(amount > 0, "Transfer amount must be greater than zero");
uint256 taxAmount = 0;
if (from != owner() && to != owner()) {
require(!bots[from] && !bots[to]);
taxAmount = amount
.mul(
(_buyCount > _reduceBuyTaxAt)
? _finalBuyTax
: _initialBuyTax
)
.div(100);
if (
from == uniswapV2Pair &&
to != address(uniswapV2Router) &&
!_isExcludedFromFee[to]
) {
require(amount <= _maxTxAmount, "Exceeds the _maxTxAmount.");
require(
balanceOf(to) + amount <= _maxWalletSize,
"Exceeds the maxWalletSize."
);
if (firstBlock + 3 > block.number) {
require(!isContract(to));
}
_buyCount++;
}
if (to != uniswapV2Pair && !_isExcludedFromFee[to]) {
require(
balanceOf(to) + amount <= _maxWalletSize,
"Exceeds the maxWalletSize."
);
}
if (to == uniswapV2Pair && from != address(this)) {
taxAmount = amount
.mul(
(_buyCount > _reduceSellTaxAt)
? _finalSellTax
: _initialSellTax
)
.div(100);
}
uint256 contractTokenBalance = balanceOf(address(this));
if (
!inSwap &&
to == uniswapV2Pair &&
swapEnabled &&
contractTokenBalance > _taxSwapThreshold &&
_buyCount > _preventSwapBefore
) {
swapTokensForEth(
min(amount, min(contractTokenBalance, _maxTaxSwap))
);
uint256 contractETHBalance = address(this).balance;
if (contractETHBalance > 0) {
sendETHToFee(address(this).balance);
}
}
}
if (taxAmount > 0) {
_balances[address(this)] = _balances[address(this)].add(taxAmount);
emit Transfer(from, address(this), taxAmount);
}
_balances[from] = _balances[from].sub(amount);
_balances[to] = _balances[to].add(amount.sub(taxAmount));
emit Transfer(from, to, amount.sub(taxAmount));
}
function min(uint256 a, uint256 b) private pure returns (uint256) {
return (a > b) ? b : a;
}
function isContract(address account) private view returns (bool) {
uint256 size;
assembly {
size := extcodesize(account)
}
return size > 0;
}
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,
address(this),
block.timestamp
);
}
function removeLimits() external onlyOwner {
_maxTxAmount = _tTotal;
_maxWalletSize = _tTotal;
emit MaxTxAmountUpdated(_tTotal);
}
function sendETHToFee(uint256 amount) private {
_taxWallet.transfer(amount);
}
function addBots(address[] memory bots_) public onlyOwner {
for (uint256 i = 0; i < bots_.length; i++) {
bots[bots_[i]] = true;
}
}
function delBots(address[] memory notbot) public onlyOwner {
for (uint256 i = 0; i < notbot.length; i++) {
bots[notbot[i]] = false;
}
}
function isBot(address a) public view returns (bool) {
return bots[a];
}
function openTrading() external onlyOwner {
require(!tradingOpen, "trading is already open");
uniswapV2Router = IUniswapV2Router02(
0x4752ba5DBc23f44D87826276BF6Fd6b1C372aD24
);
_approve(address(this), address(uniswapV2Router), _tTotal);
uniswapV2Pair = IUniswapV2Factory(uniswapV2Router.factory()).createPair(
address(this),
uniswapV2Router.WETH()
);
uniswapV2Router.addLiquidityETH{value: address(this).balance}(
address(this),
balanceOf(address(this)),
0,
0,
owner(),
block.timestamp
);
IERC20(uniswapV2Pair).approve(
address(uniswapV2Router),
type(uint256).max
);
swapEnabled = true;
tradingOpen = true;
firstBlock = block.number;
}
receive() external payable {}
}