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.
Q: Context: 'Hi;  I thought I was getting 2 firewoods, 2 waters and one food. Is that what we agreed upon?' 'You said you would give me 2 waters and 1 food for your 2 firewoods ' 'Yes, does that work for you.  I could give you 1 water and 2 foods as I really need the water for my hike.  I tend to overheat easily. '
Utterance: 'You are flipping it around. I can't give you 2 water and 2 firewood as that wouldn't really be fair '
A: 
Yes