contract MyToken {
    mapping(address => uint) public balanceOf;
    uint public totalSupply;
    string public symbol = "TKN";

    function mint(address to, uint amount) public {
        balanceOf[to] += amount;
        totalSupply += amount;
    }

    function transfer(address from, address to, uint amount) public {
        require(balanceOf[from] >= amount, "Insufficient balance");
        balanceOf[from] -= amount;
        balanceOf[to] += amount;
    }
}