contract TokenERC20  is ERC20Basic{
    // Public variables of the token
    string public name;
    string public symbol;
    uint8 public decimals = 4;
    uint256 _supply;
    mapping (address => uint256)   _balances;
    mapping (address => mapping (address => uint256)) _allowance;

    /**
     * Constrctor function
     *
     * Initializes contract with initial supply tokens to the creator of the contract
     */
    function TokenERC20(
        uint256 initialSupply,
        string tokenName,
        string tokenSymbol,
        uint8 decimal
    ) public {
        _supply = initialSupply * 10 ** uint256(decimal);  // Update total supply with the decimal amount
        _balances[msg.sender] = _supply;                // Give the creator all initial tokens
        name = tokenName;                                   // Set the name for display purposes
        symbol = tokenSymbol;                               // Set the symbol for display purposes
        decimals = decimal;
    }
    function totalSupply() public constant returns (uint256) {
        return _supply;
    }
    function balanceOf(address src) public constant returns (uint256) {
        return _balances[src];
    }
    function allowance(address src, address guy) public constant returns (uint256) {
        return _allowance[src][guy];
    }
    /**
     * Internal transfer, only can be called by this contract
     */
    function _transfer(address _from, address _to, uint _value) internal {
        // Prevent transfer to 0x0 address. Use burn() instead
        require(_to != 0x0);
        // Check if the sender has enough
        require(_balances[_from] >= _value);
        // Check for overflows
        require(_balances[_to] + _value > _balances[_to]);
        // Save this for an assertion in the future
        uint previousBalances = _balances[_from] + _balances[_to];
        // Subtract from the sender
        _balances[_from] -= _value;
        // Add the same to the recipient
        _balances[_to] += _value;
        Transfer(_from, _to, _value);
        // Asserts are used to use static analysis to find bugs in your code. They should never fail
        assert(_balances[_from] + _balances[_to] == previousBalances);
    }

    /**
     * Transfer tokens
     *
     * Send `_value` tokens to `_to` from your account
     *
     * @param _to The address of the recipient
     * @param _value the amount to send
     */
    function transfer(address _to, uint256 _value) public returns (bool){
        _transfer(msg.sender, _to, _value);
        return true;
    }

    /**
     * Transfer tokens from other address
     *
     * Send `_value` tokens to `_to` in behalf of `_from`
     *
     * @param _from The address of the sender
     * @param _to The address of the recipient
     * @param _value the amount to send
     */
    function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
        require(_value <= _allowance[_from][msg.sender]);     // Check allowance
        _allowance[_from][msg.sender] -= _value;
        _transfer(_from, _to, _value);
        return true;
    }

    /**
     * Set allowance for other address
     *
     * Allows `_spender` to spend no more than `_value` tokens in your behalf
     *
     * @param _spender The address authorized to spend
     * @param _value the max amount they can spend
     */
    function approve(address _spender, uint256 _value) public returns (bool success) {
        _allowance[msg.sender][_spender] = _value;
        return true;
    }

    /**
     * Set allowance for other address and notify
     *
     * Allows `_spender` to spend no more than `_value` tokens in your behalf, and then ping the contract about it
     *
     * @param _spender The address authorized to spend
     * @param _value the max amount they can spend
     */
    function approveAndCall(address _spender, uint256 _value)
        public returns (bool success) {
        if (approve(_spender, _value)) {
            Approval(msg.sender, _spender, _value);
            return true;
        }
    }

    /**
     * Destroy tokens
     *
     * Remove `_value` tokens from the system irreversibly
     *
     * @param _value the amount of money to burn
     */
    function burn(uint256 _value) public returns (bool success) {
        require(_balances[msg.sender] >= _value);   // Check if the sender has enough
        _balances[msg.sender] -= _value;            // Subtract from the sender
        _supply -= _value;                      // Updates totalSupply
        Burn(msg.sender, _value);
        return true;
    }

    /**
     * Destroy tokens from other account
     *
     * Remove `_value` tokens from the system irreversibly on behalf of `_from`.
     *
     * @param _from the address of the sender
     * @param _value the amount of money to burn
     */
    function burnFrom(address _from, uint256 _value) public returns (bool success) {
        require(_balances[_from] >= _value);                // Check if the targeted balance is enough
        require(_value <= _allowance[_from][msg.sender]);    // Check allowance
        _balances[_from] -= _value;                         // Subtract from the targeted balance
        _allowance[_from][msg.sender] -= _value;             // Subtract from the sender's allowance
        _supply -= _value;                              // Update totalSupply
        Burn(_from, _value);
        return true;
    }
}
function burn(uint256 _value) public returns (bool success) {
        require(_balances[msg.sender] >= _value);   // Check if the sender has enough
        _balances[msg.sender] -= _value;            // Subtract from the sender
        _supply -= _value;                      // Updates totalSupply
        Burn(msg.sender, _value);
        return true;
    }
/**
 * Destroy tokens
 *
 * Remove `_value` tokens from the system irreversibly
 *
 * @param _value the amount of money to burn
 */