The input is taken from a negotiation between two participants who take the role of campsite neighbors and negotiate for Food, Water, and Firewood packages, based on their individual preferences and requirements. Given an utterance and recent dialogue context containing past 3 utterances (wherever available), output Yes if the utterance contains the vouch-fair strategy, otherwise output No. vouch-fair is a selfish negotiation strategy. It is used to call out fairness for personal benefit, either when acknowledging a fair deal or when the opponent offers a deal that benefits them. This can be through an explicit call out or can be implied.

Example Input: Context: 'I need firewood to cook the fish I plan to catch.  I don't really need more food, but I can use a little water too, since it's warm.' 'I need firewood, because I have a medical condition that causes my veins to close if I get too cold at night. I don't mind sharing the water.' 'I could give you 1 firewood, 2 waters, and 1 food. '
Utterance: 'If you make it two food, we have a deal.'
Example Output: No

Example Input: Context: 'hello' 'hi'
Utterance: 'In this extra package I need two food'
Example Output: No

Example Input: Context: 'Hey, Nice getting to interact with you. I would need additional packages of food as I'm camping with Family and my kids tend to get hungry often.' 'I also have a family I am camping with several small childern and my wife who is pregnant. I need plenty of firewood and water.'
Utterance: 'I get it, in that case and to be a fair deal. I will have 2 of food, 1 of water and firewood each.'
Example Output:
Yes