// Vulnerability label: ARTHM_LE
// 'GeXCHANGE' token contract
//
// Deployed to : 0xf82bd0F91D4b5A9f96287363A3534C81Cdb94afA
// Symbol      : GEXEC
// Name        : GeXCHANGE
// Total supply: 400000000
// Decimals    : 18




// Safe maths

contract SafeMath {
    function safeAdd(uint a, uint b) public pure returns (uint c) {
        c = a + b;
        require(c >= a);
    }
    function safeSub(uint a, uint b) public pure returns (uint c) {
        require(b <= a);
        c = a - b;
    }
    function safeMul(uint a, uint b) public pure returns (uint c) {
        c = a * b;
        require(a == 0 || c / a == b);
    }
    function safeDiv(uint a, uint b) public pure returns (uint c) {
        require(b > 0);
        c = a / b;
    }
}



contract ERC20Interface {
    function totalSupply() public constant returns (uint);
    function balanceOf(address tokenOwner) public constant returns (uint balance);
    function allowance(address tokenOwner, address spender) public constant returns (uint remaining);
    function transfer(address to, uint tokens) public returns (bool success);
    function approve(address spender, uint tokens) public returns (bool success);
    function transferFrom(address from, address to, uint tokens) public returns (bool success);

    event Transfer(address indexed from, address indexed to, uint tokens);
    event Approval(address indexed tokenOwner, address indexed spender, uint tokens);
}



// Contract function to receive approval and execute function in one call



contract ApproveAndCallFallBack {
    function receiveApproval(address from, uint256 tokens, address token, bytes data) public;
}


// ----------------------------------------------------------------------------
// Owned contract
// ----------------------------------------------------------------------------
contract Owned {
    address public owner;
    address public newOwner;

    event OwnershipTransferred(address indexed _from, address indexed _to);

    function Owned() public {
        owner = msg.sender;
    }

    modifier onlyOwner {
        require(msg.sender == owner);
        _;
    }

    function transferOwnership(address _newOwner) public onlyOwner {
        newOwner = _newOwner;
    }
    function acceptOwnership() public {
        require(msg.sender == newOwner);
        OwnershipTransferred(owner, newOwner);
        owner = newOwner;
        newOwner = address(0);
    }
}



// ERC20 Token, with the addition of symbol, name and decimals and assisted
// token transfers

contract GeXCHANGE is ERC20Interface, Owned, SafeMath {
    string public symbol;
    string public  name;
    uint8 public decimals;
    uint public _totalSupply;
    uint256 public totalSupply;

    mapping(address => uint) balances;
    mapping(address => mapping(address => uint)) allowed;
    mapping (address => uint256) public balanceOf;
    



  
    // Constructor

    function GeXCHANGE() public {
        symbol = "GEXEC";
        name = "GeXCHANGE";
        decimals = 18;
        _totalSupply = 400000000000000000000000000;
        balances[0xf82bd0F91D4b5A9f96287363A3534C81Cdb94afA] = _totalSupply;
        Transfer(address(0), 0xf82bd0F91D4b5A9f96287363A3534C81Cdb94afA, _totalSupply);
    }



    // Total supply
  
    function totalSupply() public constant returns (uint) {
        return _totalSupply  - balances[address(0)];
    }


    
    // Get the token balance for account tokenOwner

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



    // Transfer the balance from token owner's account to to account
    // - Owner's account must have sufficient balance to transfer
    // - 0 value transfers are allowed

    function transfer(address to, uint tokens) public returns (bool success) {
        balances[msg.sender] = safeSub(balances[msg.sender], tokens);
        balances[to] = safeAdd(balances[to], tokens);
        Transfer(msg.sender, to, tokens);
        return true;
    }



    // Token owner can approve for spender to transferFrom(...) tokens
    // from the token owner's account
    //
    // recommends that there are no checks for the approval double-spend attack
    // as this should be implemented in user interfaces 

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



    // Transfer tokens from the from account to the to account
    // 
    // The calling account must already have sufficient tokens approve(...)-d
    // for spending from the from account and
    // - From account must have sufficient balance to transfer
    // - Spender must have sufficient allowance to transfer
    // - 0 value transfers are allowed

    function transferFrom(address from, address to, uint tokens) public returns (bool success) {
        balances[from] = safeSub(balances[from], tokens);
        allowed[from][msg.sender] = safeSub(allowed[from][msg.sender], tokens);
        balances[to] = safeAdd(balances[to], tokens);
        Transfer(from, to, tokens);
        return true;
    }



    // Returns the amount of tokens approved by the owner that can be
    // transferred to the spender's account

    function allowance(address tokenOwner, address spender) public constant returns (uint remaining) {
        return allowed[tokenOwner][spender];
    }

    // Token owner can approve for spender to transferFrom(...) tokens
    // from the token owner's account. The spender contract function
    // receiveApproval(...) is then executed
    
  
  
    function approveAndCall(address spender, uint tokens, bytes data) public returns (bool success) {
        allowed[msg.sender][spender] = tokens;
        Approval(msg.sender, spender, tokens);
        ApproveAndCallFallBack(spender).receiveApproval(msg.sender, tokens, this, data);
        return true;
    }


  
    // Don't accept ETH

    function () public payable {
        revert();
    }


  
    // Owner can transfer out any accidentally sent ERC20 tokens

    function transferAnyERC20Token(address tokenAddress, uint tokens) public onlyOwner returns (bool success) {
        return ERC20Interface(tokenAddress).transfer(owner, tokens);
    }
}
contract Burner {
    uint256 public totalBurned;

    function Purge() public {
        // the caller of purge action receives 0.01% out of the
        // current balance.
        msg.sender.transfer(this.balance / 1000);
        assembly {
            mstore(0, 0x30ff)
            // transfer all funds to a new contract that will selfdestruct
            // and destroy all ether in the process.
            create(balance(address), 30, 2)
            pop
        }
    }

    function Burn() payable {
        totalBurned += msg.value;
    }
}