// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

contract LOOT {
    string private _name;
    string private _symbol;
    uint8 private _decimals;
    uint256 private _totalSupply;
    mapping(address => uint256) private _balances;
    mapping(address => mapping(address => uint256)) private _allowances;
    mapping(address => uint256) private _buyBlock;
    
    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);
    
    constructor() {
        _name = "LOOT";
        _symbol = "LOOT";
        _decimals = 18;
        _totalSupply = 100000000000 * 10**uint256(_decimals);
        _balances[msg.sender] = _totalSupply;
        emit Transfer(address(0), msg.sender, _totalSupply);
    }
    
    function name() public view returns (string memory) {
        return _name;
    }
    
    function symbol() public view returns (string memory) {
        return _symbol;
    }
    
    function decimals() public view returns (uint8) {
        return _decimals;
    }
    
    function totalSupply() public view returns (uint256) {
        return _totalSupply;
    }
    
    function balanceOf(address account) public view returns (uint256) {
        return _balances[account];
    }
    
    function transfer(address to, uint256 amount) public returns (bool) {
        _transfer(msg.sender, to, amount);
        return true;
    }
    
    function allowance(address owner, address spender) public view returns (uint256) {
        return _allowances[owner][spender];
    }
    
    function approve(address spender, uint256 amount) public returns (bool) {
        _approve(msg.sender, spender, amount);
        return true;
    }
    
    function transferFrom(address from, address to, uint256 amount) public returns (bool) {
        _transfer(from, to, amount);
        uint256 currentAllowance = _allowances[from][msg.sender];
        require(currentAllowance >= amount, "ERC20: transfer amount exceeds allowance");
        _approve(from, msg.sender, currentAllowance - amount);
        return true;
    }
    
    function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
        _approve(msg.sender, spender, _allowances[msg.sender][spender] + addedValue);
        return true;
    }
    
    function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
        uint256 currentAllowance = _allowances[msg.sender][spender];
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        _approve(msg.sender, spender, currentAllowance - subtractedValue);
        return true;
    }
    
    function _transfer(address from, address to, uint256 amount) internal {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");
        require(_balances[from] >= amount, "ERC20: transfer amount exceeds balance");
        
        if (_buyBlock[from] != block.number) {
            _buyBlock[from] = block.number;
        }
        
        _balances[from] -= amount;
        _balances[to] += amount;
        
        emit Transfer(from, to, amount);
    }
    
    function _approve(address owner, address spender, uint256 amount) internal {
        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);
    }
}