TASK DEFINITION: Given a negotiation between two participants, answer 'Yes' if both participants agree to the deal, otherwise answer 'No'.
PROBLEM: THEM: i can part with the hats but would like the book and ball YOU: i can not part with the ball but can split the hats or book. THEM: i must have the book... i can cede all others YOU: you an have the books if i can have the others. THEM: deal.

SOLUTION: No

PROBLEM: THEM: i want the balls. i can offer you the rest. YOU: can i have 1 ball and give you a book for it? THEM: 2 balls and a book to me? if so that works for me.

SOLUTION: Yes

PROBLEM: THEM: i want the hats and book YOU: you can have hats but i want the rest THEM: i want one more item to go with my hats YOU: how about one ball and two hats for you? THEM: ok deal.

SOLUTION:
Yes