data_full/CVE_clean/2018-12083.sol

pragma solidity ^0.4.18;
contract owned {
	address public owner;
	function owned() {
		owner = msg.sender;
	}
	function changeOwner(address newOwner) onlyOwner {
		owner = newOwner;
	}
	modifier onlyOwner {
		require(msg.sender == owner);
		_;
	}
}
contract tokenRecipient { function receiveApproval(address _from, uint256 _value, address _token, bytes _extraData); }
contract GoalToken is owned {
    string public name = "GOAL Bonanza";
    string public symbol = "GOAL";
    uint8 public decimals = 18;
    uint256 public totalSupply = 0;
    mapping (address => uint256) public balanceOf;
    mapping (address => mapping (address => uint256)) public allowance;
    event Transfer(address indexed from, address indexed to, uint256 value);
    event Burn(address indexed from, uint256 value);
    function _transfer(address _from, address _to, uint _value) internal {
        require (_to != 0x0);                               
        require (balanceOf[_from] > _value);                
        require (balanceOf[_to] + _value > balanceOf[_to]); 
        balanceOf[_from] -= _value;                         
        balanceOf[_to] += _value;                            
        Transfer(_from, _to, _value);
    }
    function transfer(address _to, uint256 _value) {
        _transfer(msg.sender, _to, _value);
    }
    function transferFrom(address _from, address _to, uint256 _value) returns (bool success) {
        require (_value <= allowance[_from][msg.sender]);     
        allowance[_from][msg.sender] -= _value;
        _transfer(_from, _to, _value);
        return true;
    }
    function approve(address _spender, uint256 _value)
        returns (bool success) {
        allowance[msg.sender][_spender] = _value;
        return true;
    }
    function approveAndCall(address _spender, uint256 _value, bytes _extraData)
        returns (bool success) {
        tokenRecipient spender = tokenRecipient(_spender);
        if (approve(_spender, _value)) {
            spender.receiveApproval(msg.sender, _value, this, _extraData);
            return true;
        }
    }        
    function burn(uint256 _value) returns (bool success) {
        require (balanceOf[msg.sender] > _value);            
        balanceOf[msg.sender] -= _value;                      
        totalSupply -= _value;                                
        Burn(msg.sender, _value);
        return true;
    }
    function burnFrom(address _from, uint256 _value) returns (bool success) {
        require(balanceOf[_from] >= _value);                
        require(_value <= allowance[_from][msg.sender]);    
        balanceOf[_from] -= _value;                         
        allowance[_from][msg.sender] -= _value;             
        totalSupply -= _value;                              
        Burn(_from, _value);
        return true;
    }
    function mintToken(address target, uint256 mintedAmount) onlyOwner {
        balanceOf[target] += mintedAmount;
        totalSupply += mintedAmount;
        Transfer(this, target, mintedAmount);
    }
}