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: 
Utterance: 'Hello! camper, how are you? I need us to make a deal where we all benefit.I'm so excited for our camping trip.  I'm most excited about getting to eat food that I normally don't when I am home.🙂'
Example Output: Yes

Example Input: Context: 'Hello! I believe that we can help each other here.' 'hi how are you, what help you need?'
Utterance: 'Lets strike balance like 1/2 2/1 3/0'
Example Output: Yes

Example Input: Context: 'I am looking for one of each. Food I am especially looking for.' 'That sounds pretty reasonable as I am in need of firewood the most. Would it be most reasonable to each take what we need most and split the water down the middle?' 'Yes, it would.'
Utterance: 'I think that sounds fair. The problem is that there are 3 waters and one of us would get two and the other one. How should we sort that?'
Example Output:
Yes