contract Ownable {
    //Variables
    address public owner;

    address public newOwner;

    //    Modifiers
    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(msg.sender == owner);
        _;
    }

    /**
     * @dev The Ownable constructor sets the original `owner` of the contract to the sender
     * account.
     */
    function Ownable() public {
        owner = msg.sender;
    }

    /**
     * @dev Allows the current owner to transfer control of the contract to a newOwner.
     * @param _newOwner The address to transfer ownership to.
     */
    function transferOwnership(address _newOwner) public onlyOwner {
        require(_newOwner != address(0));
        newOwner = _newOwner;

    }

    function acceptOwnership() public {
        if (msg.sender == newOwner) {
            owner = newOwner;
        }
    }
}
/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
 */
function Ownable() public {
    owner = msg.sender;
}

/**
 * @dev The Ownable constructor sets the original `owner` of the contract to the sender
 * account.
 */