Forkchoice Ethereum Mainnet

/**
 *Submitted for verification at Etherscan.io on 2020-02-27
*/

pragma solidity 0.4.19;


contract RegularToken{

    function transfer(address _to, uint _value) public returns (bool) {
        //Default assumes totalSupply can't be over max (2^256 - 1).
        if (balances[msg.sender] >= _value && balances[_to] + _value >= balances[_to]) {
            balances[msg.sender] -= _value;
            balances[_to] += _value;
            Transfer(msg.sender, _to, _value);
            return true;
        } else { revert(); }
    }

    function transferFrom(address _from, address _to, uint _value) public returns (bool) {
        if (balances[_from] >= _value && allowed[_from][msg.sender] >= _value && balances[_to] + _value >= balances[_to]) {
            balances[_to] += _value;
            balances[_from] -= _value;
            allowed[_from][msg.sender] -= _value;
            Transfer(_from, _to, _value);
            return true;
        } else { revert(); }
    }

    function balanceOf(address _owner) constant public returns (uint) {
        return balances[_owner];
    }

    function approve(address _spender, uint _value) public returns (bool) {
        allowed[msg.sender][_spender] = _value;
        Approval(msg.sender, _spender, _value);
        return true;
    }

    function allowance(address _owner, address _spender) constant public returns (uint) {
        return allowed[_owner][_spender];
    }


    mapping (address => uint) balances;
    mapping (address => mapping (address => uint)) allowed;
    uint public totalSupply;

    event Transfer(address indexed _from, address indexed _to, uint _value);
    event Approval(address indexed _owner, address indexed _spender, uint _value);
}

contract UnboundedRegularToken is RegularToken {

    uint constant MAX_UINT = 2**256 - 1;
    
    /// @dev ERC20 transferFrom, modified such that an allowance of MAX_UINT represents an unlimited amount.
    /// @param _from Address to transfer from.
    /// @param _to Address to transfer to.
    /// @param _value Amount to transfer.
    /// @return Success of transfer.
    function transferFrom(address _from, address _to, uint _value)
        public
        returns (bool)
    {
        uint allowance = allowed[_from][msg.sender];
        if (balances[_from] >= _value
            && allowance >= _value
            && balances[_to] + _value >= balances[_to]
        ) {
            balances[_to] += _value;
            balances[_from] -= _value;
            if (allowance < MAX_UINT) {
                allowed[_from][msg.sender] -= _value;
            }
            Transfer(_from, _to, _value);
            return true;
        } else {
            revert();
        }
    }
}

contract HBToken is UnboundedRegularToken {

    uint8 constant public decimals = 8;
    string constant public name = "Hubble";
    string constant public symbol = "HB";

    function HBToken() public {
        totalSupply = 678000000 * 10 ** uint256(decimals);
        balances[msg.sender] = totalSupply;
        Transfer(address(0), msg.sender, totalSupply);
    }
}