/**
*Submitted for verification at BscScan.com on 2021-11-15
*/

// SPDX-License-Identifier: MIT

pragma solidity 0.8.9;

abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}

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

interface IUniswapV2Pair {
event Approval(address indexed owner, address indexed spender, uint value);
event Transfer(address indexed from, address indexed to, uint value);

function name() external pure returns (string memory);
function symbol() external pure returns (string memory);
function decimals() external pure returns (uint8);
function totalSupply() external view returns (uint);
function balanceOf(address owner) external view returns (uint);
function allowance(address owner, address spender) external view returns (uint);

function approve(address spender, uint value) external returns (bool);
function transfer(address to, uint value) external returns (bool);
function transferFrom(address from, address to, uint value) external returns (bool);

function DOMAIN_SEPARATOR() external view returns (bytes32);
function PERMIT_TYPEHASH() external pure returns (bytes32);
function nonces(address owner) external view returns (uint);

function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;

event Mint(address indexed sender, uint amount0, uint amount1);
event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
event Swap(
address indexed sender,
uint amount0In,
uint amount1In,
uint amount0Out,
uint amount1Out,
address indexed to
);
event Sync(uint112 reserve0, uint112 reserve1);

function MINIMUM_LIQUIDITY() external pure returns (uint);
function factory() external view returns (address);
function token0() external view returns (address);
function token1() external view returns (address);
function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
function price0CumulativeLast() external view returns (uint);
function price1CumulativeLast() external view returns (uint);
function kLast() external view returns (uint);

function mint(address to) external returns (uint liquidity);
function burn(address to) external returns (uint amount0, uint amount1);
function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
function skim(address to) external;
function sync() external;

function initialize(address, address) 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;
}

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);
}

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);
}


contract ERC20 is Context, IERC20, IERC20Metadata {
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;

/**
* @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);
_approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: 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 {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].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 {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) {
_approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
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 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);

_balances[sender] = _balances[sender].sub(amount, "ERC20: 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:
*
* - `account` cannot be the zero address.
*/
function _mint(address account, uint256 amount) internal virtual {
require(account != address(0), "ERC20: mint to the zero address");

_beforeTokenTransfer(address(0), account, amount);

_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 virtual {
require(account != address(0), "ERC20: burn from the zero address");

_beforeTokenTransfer(account, address(0), amount);

_balances[account] = _balances[account].sub(amount, "ERC20: 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 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 to 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 {}
}

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;
}
}

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 () {
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;
}
}



library SafeMathInt {
int256 private constant MIN_INT256 = int256(1) << 255;
int256 private constant MAX_INT256 = ~(int256(1) << 255);

/**
* @dev Multiplies two int256 variables and fails on overflow.
*/
function mul(int256 a, int256 b) internal pure returns (int256) {
int256 c = a * b;

// Detect overflow when multiplying MIN_INT256 with -1
require(c != MIN_INT256 || (a & MIN_INT256) != (b & MIN_INT256));
require((b == 0) || (c / b == a));
return c;
}

/**
* @dev Division of two int256 variables and fails on overflow.
*/
function div(int256 a, int256 b) internal pure returns (int256) {
// Prevent overflow when dividing MIN_INT256 by -1
require(b != -1 || a != MIN_INT256);

// Solidity already throws when dividing by 0.
return a / b;
}

/**
* @dev Subtracts two int256 variables and fails on overflow.
*/
function sub(int256 a, int256 b) internal pure returns (int256) {
int256 c = a - b;
require((b >= 0 && c <= a) || (b < 0 && c > a));
return c;
}

/**
* @dev Adds two int256 variables and fails on overflow.
*/
function add(int256 a, int256 b) internal pure returns (int256) {
int256 c = a b;
require((b >= 0 && c >= a) || (b < 0 && c < a));
return c;
}

/**
* @dev Converts to absolute value, and fails on overflow.
*/
function abs(int256 a) internal pure returns (int256) {
require(a != MIN_INT256);
return a < 0 ? -a : a;
}


function toUint256Safe(int256 a) internal pure returns (uint256) {
require(a >= 0);
return uint256(a);
}
}

library SafeMathUint {
function toInt256Safe(uint256 a) internal pure returns (int256) {
int256 b = int256(a);
require(b >= 0);
return b;
}
}


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;
}

contract XRXS is ERC20, Ownable {
using SafeMath for uint256;

IUniswapV2Router02 public immutable uniswapV2Router;
address public immutable uniswapV2Pair;
address public constant deadAddress = address(0xdead);

bool private swapping;

address public marketingWallet;
address public buyBackWallet;

uint256 public maxTransactionAmount;
uint256 public swapTokensAtAmount;
uint256 public maxWallet;

bool public limitsInEffect = true;
bool public tradingActive = false;
bool public swapEnabled = false;

uint256 public tradingActiveBlock;

// Anti-bot and anti-whale mappings and variables
mapping(address => uint256) private _holderLastTransferTimestamp; // to hold last Transfers temporarily during launch
bool public transferDelayEnabled = true;

uint256 public buyTotalFees;
uint256 public buyMarketingFee;
uint256 public buyLiquidityFee;
uint256 public buyBuyBackFee;

uint256 public sellTotalFees;
uint256 public sellMarketingFee;
uint256 public sellLiquidityFee;
uint256 public sellBuyBackFee;

uint256 public tokensForMarketing;
uint256 public tokensForLiquidity;
uint256 public tokensForBuyBack;

/******************/

// exlcude from fees and max transaction amount
mapping (address => bool) private _isExcludedFromFees;
mapping (address => bool) public _isExcludedMaxTransactionAmount;

// store addresses that a automatic market maker pairs. Any transfer *to* these addresses
// could be subject to a maximum transfer amount
mapping (address => bool) public automatedMarketMakerPairs;

event UpdateUniswapV2Router(address indexed newAddress, address indexed oldAddress);

event ExcludeFromFees(address indexed account, bool isExcluded);

event SetAutomatedMarketMakerPair(address indexed pair, bool indexed value);

event marketingWalletUpdated(address indexed newWallet, address indexed oldWallet);

event buyBackWalletUpdated(address indexed newWallet, address indexed oldWallet);

event SwapAndLiquify(
uint256 tokensSwapped,
uint256 ethReceived,
uint256 tokensIntoLiquidity
);

event BuyBackTriggered(uint256 amount);

constructor() ERC20("XRXS", "XRXS") {

address newOwner = address(0xc33191a0A2596813D01842A43c4fb781Ff793c08);

IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0x10ED43C718714eb63d5aA57B78B54704E256024E);

excludeFromMaxTransaction(address(_uniswapV2Router), true);
uniswapV2Router = _uniswapV2Router;

uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory()).createPair(address(this), _uniswapV2Router.WETH());
excludeFromMaxTransaction(address(uniswapV2Pair), true);
_setAutomatedMarketMakerPair(address(uniswapV2Pair), true);

uint256 _buyMarketingFee = 3;
uint256 _buyLiquidityFee = 3;
uint256 _buyBuyBackFee = 2;

// 30% sell tax to start, will be reduced over time.

uint256 _sellMarketingFee = 4;
uint256 _sellLiquidityFee = 4;
uint256 _sellBuyBackFee = 4;

uint256 totalSupply = 1 * 1e9 * 1e18;

maxTransactionAmount = totalSupply * 1 / 1000; // 0.1% maxTransactionAmountTxn
swapTokensAtAmount = totalSupply * 5 / 10000; // 0.05% swap wallet
maxWallet = totalSupply * 5 / 1000; // 0.5% max wallet

buyMarketingFee = _buyMarketingFee;
buyLiquidityFee = _buyLiquidityFee;
buyBuyBackFee = _buyBuyBackFee;
buyTotalFees = buyMarketingFee buyLiquidityFee buyBuyBackFee;

sellMarketingFee = _sellMarketingFee;
sellLiquidityFee = _sellLiquidityFee;
sellBuyBackFee = _sellBuyBackFee;
sellTotalFees = sellMarketingFee sellLiquidityFee sellBuyBackFee;

marketingWallet = address(0x3A23ACf34007De8F3f234d7e465722481508B6c9); // set as marketing wallet
buyBackWallet = address(0xc33191a0A2596813D01842A43c4fb781Ff793c08); // set as buyback wallet

// exclude from paying fees or having max transaction amount
excludeFromFees(newOwner, true);
excludeFromFees(address(this), true);
excludeFromFees(address(0xdead), true);
excludeFromFees(buyBackWallet, true);

excludeFromMaxTransaction(newOwner, true);
excludeFromMaxTransaction(address(this), true);
excludeFromMaxTransaction(buyBackWallet, true);
excludeFromMaxTransaction(address(0xdead), true);

/*
_mint is an internal function in ERC20.sol that is only called here,
and CANNOT be called ever again
*/
_mint(newOwner, totalSupply);
transferOwnership(newOwner);
}

receive() external payable {

}

// once enabled, can never be turned off
function enableTrading() external onlyOwner {
tradingActive = true;
swapEnabled = true;
tradingActiveBlock = block.number;
}

// remove limits after token is stable
function removeLimits() external onlyOwner returns (bool){
limitsInEffect = false;
return true;
}

// disable Transfer delay - cannot be reenabled
function disableTransferDelay() external onlyOwner returns (bool){
transferDelayEnabled = false;
return true;
}

// change the minimum amount of tokens to sell from fees
function updateSwapTokensAtAmount(uint256 newAmount) external onlyOwner returns (bool){
require(newAmount >= totalSupply() * 1 / 100000, "Swap amount cannot be lower than 0.001% total supply.");
require(newAmount <= totalSupply() * 5 / 1000, "Swap amount cannot be higher than 0.5% total supply.");
swapTokensAtAmount = newAmount;
return true;
}

function updateMaxAmount(uint256 newNum) external onlyOwner {
require(newNum >= (totalSupply() * 5 / 1000)/1e18, "Cannot set maxTransactionAmount lower than 0.5%");
maxTransactionAmount = newNum * (10**18);
}

function excludeFromMaxTransaction(address updAds, bool isEx) public onlyOwner {
_isExcludedMaxTransactionAmount[updAds] = isEx;
}

// only use to disable contract sales if absolutely necessary (emergency use only)
function updateSwapEnabled(bool enabled) external onlyOwner(){
swapEnabled = enabled;
}

function updateBuyFees(uint256 _marketingFee, uint256 _liquidityFee, uint256 _buyBackFee) external onlyOwner {
buyMarketingFee = _marketingFee;
buyLiquidityFee = _liquidityFee;
buyBuyBackFee = _buyBackFee;
buyTotalFees = buyMarketingFee buyLiquidityFee buyBuyBackFee;
require(buyTotalFees <= 15, "Must keep fees at 15% or less");
}

function updateSellFees(uint256 _marketingFee, uint256 _liquidityFee, uint256 _buyBackFee) external onlyOwner {
sellMarketingFee = _marketingFee;
sellLiquidityFee = _liquidityFee;
sellBuyBackFee = _buyBackFee;
sellTotalFees = sellMarketingFee sellLiquidityFee sellBuyBackFee;
require(sellTotalFees <= 15, "Must keep fees at 30% or less");
}

function excludeFromFees(address account, bool excluded) public onlyOwner {
_isExcludedFromFees[account] = excluded;
emit ExcludeFromFees(account, excluded);
}

function setAutomatedMarketMakerPair(address pair, bool value) public onlyOwner {
require(pair != uniswapV2Pair, "The pair cannot be removed from automatedMarketMakerPairs");

_setAutomatedMarketMakerPair(pair, value);
}

function _setAutomatedMarketMakerPair(address pair, bool value) private {
automatedMarketMakerPairs[pair] = value;

emit SetAutomatedMarketMakerPair(pair, value);
}

function updateMarketingWallet(address newMarketingWallet) external onlyOwner {
emit marketingWalletUpdated(newMarketingWallet, marketingWallet);
marketingWallet = newMarketingWallet;
}

function updateBuyBackWallet(address newWallet) external onlyOwner {
emit buyBackWalletUpdated(newWallet, buyBackWallet);
buyBackWallet = newWallet;
}


function isExcludedFromFees(address account) public view returns(bool) {
return _isExcludedFromFees[account];
}

event BoughtEarly(address indexed sniper);

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;
}

if(limitsInEffect){
if (
from != owner() &&
to != owner() &&
to != address(0) &&
to != address(0xdead) &&
!swapping
){
if(!tradingActive){
require(_isExcludedFromFees[from] || _isExcludedFromFees[to], "Trading is not active.");
}

// at launch if the transfer delay is enabled, ensure the block timestamps for purchasers is set -- during launch.
if (transferDelayEnabled){
if (to != owner() && to != address(uniswapV2Router) && to != address(uniswapV2Pair)){
require(_holderLastTransferTimestamp[tx.origin] < block.number, "_transfer:: Transfer Delay enabled. Only one purchase per block allowed.");
_holderLastTransferTimestamp[tx.origin] = block.number;
}
}

//when buy
if (automatedMarketMakerPairs[from] && !_isExcludedMaxTransactionAmount[to]) {
require(amount <= maxTransactionAmount, "Buy transfer amount exceeds the maxTransactionAmount.");
require(amount balanceOf(to) <= maxWallet, "Max wallet exceeded");
}

//when sell
else if (automatedMarketMakerPairs[to] && !_isExcludedMaxTransactionAmount[from]) {
require(amount <= maxTransactionAmount, "Sell transfer amount exceeds the maxTransactionAmount.");
}
else {
require(amount balanceOf(to) <= maxWallet, "Max wallet exceeded");
}
}
}



uint256 contractTokenBalance = balanceOf(address(this));

bool canSwap = contractTokenBalance >= swapTokensAtAmount;

if(
canSwap &&
swapEnabled &&
!swapping &&
!automatedMarketMakerPairs[from] &&
!_isExcludedFromFees[from] &&
!_isExcludedFromFees[to]
) {
swapping = true;

swapBack();

swapping = false;
}

bool takeFee = !swapping;

// if any account belongs to _isExcludedFromFee account then remove the fee
if(_isExcludedFromFees[from] || _isExcludedFromFees[to]) {
takeFee = false;
}

uint256 fees = 0;
// only take fees on buys/sells, do not take on wallet transfers
if(takeFee){
if(tradingActiveBlock 2 >= block.number && (automatedMarketMakerPairs[to] || automatedMarketMakerPairs[from])){
fees = amount.mul(99).div(100);
tokensForLiquidity = fees * 33 / 99;
tokensForBuyBack = fees * 33 / 99;
tokensForMarketing = fees * 33 / 99;
}
// on sell
else if (automatedMarketMakerPairs[to] && sellTotalFees > 0){
fees = amount.mul(sellTotalFees).div(100);
tokensForLiquidity = fees * sellLiquidityFee / sellTotalFees;
tokensForBuyBack = fees * sellBuyBackFee / sellTotalFees;
tokensForMarketing = fees * sellMarketingFee / sellTotalFees;
}
// on buy
else if(automatedMarketMakerPairs[from] && buyTotalFees > 0) {
fees = amount.mul(buyTotalFees).div(100);
tokensForLiquidity = fees * buyLiquidityFee / buyTotalFees;
tokensForBuyBack = fees * buyBuyBackFee / buyTotalFees;
tokensForMarketing = fees * buyMarketingFee / buyTotalFees;
}

if(fees > 0){
super._transfer(from, address(this), fees);
}

amount -= fees;
}

super._transfer(from, to, amount);
}

function swapTokensForEth(uint256 tokenAmount) private {

// generate the uniswap pair path of token -> weth
address[] memory path = new address[](2);
path[0] = address(this);
path[1] = uniswapV2Router.WETH();

_approve(address(this), address(uniswapV2Router), tokenAmount);

// make the swap
uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
tokenAmount,
0, // accept any amount of ETH
path,
address(this),
block.timestamp
);

}



function addLiquidity(uint256 tokenAmount, uint256 ethAmount) private {
// approve token transfer to cover all possible scenarios
_approve(address(this), address(uniswapV2Router), tokenAmount);

// add the liquidity
uniswapV2Router.addLiquidityETH{value: ethAmount}(
address(this),
tokenAmount,
0, // slippage is unavoidable
0, // slippage is unavoidable
deadAddress,
block.timestamp
);
}

function swapBack() private {
uint256 contractBalance = balanceOf(address(this));
uint256 totalTokensToSwap = tokensForLiquidity tokensForMarketing tokensForBuyBack;

if(contractBalance == 0 || totalTokensToSwap == 0) {return;}

// Halve the amount of liquidity tokens
uint256 liquidityTokens = contractBalance * tokensForLiquidity / totalTokensToSwap / 2;
uint256 amountToSwapForETH = contractBalance.sub(liquidityTokens);

uint256 initialETHBalance = address(this).balance;

swapTokensForEth(amountToSwapForETH);

uint256 ethBalance = address(this).balance.sub(initialETHBalance);

uint256 ethForMarketing = ethBalance.mul(tokensForMarketing).div(totalTokensToSwap);
uint256 ethForBuyBack = ethBalance.mul(tokensForBuyBack).div(totalTokensToSwap);


uint256 ethForLiquidity = ethBalance - ethForMarketing - ethForBuyBack;


tokensForLiquidity = 0;
tokensForMarketing = 0;
tokensForBuyBack = 0;

(bool success,) = address(marketingWallet).call{value: ethForMarketing}("");
if(liquidityTokens > 0 && ethForLiquidity > 0){
addLiquidity(liquidityTokens, ethForLiquidity);
emit SwapAndLiquify(amountToSwapForETH, ethForLiquidity, tokensForLiquidity);
}

// keep leftover ETH for buyback
(success,) = address(buyBackWallet).call{value: address(this).balance}("");
}

// useful for buybacks or to reclaim any BNB on the contract in a way that helps holders.
function buyBackTokens(uint256 bnbAmountInWei) external onlyOwner {
// generate the uniswap pair path of weth -> eth
address[] memory path = new address[](2);
path[0] = uniswapV2Router.WETH();
path[1] = address(this);

// make the swap
uniswapV2Router.swapExactETHForTokensSupportingFeeOnTransferTokens{value: bnbAmountInWei}(
0, // accept any amount of Ethereum
path,
address(0xdead),
block.timestamp
);
emit BuyBackTriggered(bnbAmountInWei);
}
}