Definition: Given a negotiation between two participants, answer 'Yes' if both participants agree to the deal, otherwise answer 'No'.
Input: THEM: i'll give you 1 book and 1 hat  YOU: how about all the balls and the book  THEM: can't do that. i'll give you 1 ball and either 1 hat or 1 book  YOU: ill take one book and one ball.
Output:
Yes