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: 'Hi! I like to hike so I really need more water. Could I take 2 packages of water and 1 of food and 2 of firewood?' 'I am ok with the water, i just would like one water and one food, but i would appreciate two firewoods, i get cold at night  '
Utterance: 'We both sound pretty reasonable! So you think you need 2 firewood?'
Example Output: Yes

Example Input: Context: 'Hi, I would like all of the water and 2 food packages. You can have all of the firewood and one food package. Does that sound good?'
Utterance: 'Nice to meet you! I definitely like the idea of having all of the firewood, but water is very important to me. Let's see if we can come to and agreement on how to split up the water.'
Example Output: Yes

Example Input: Context: 'I also need the water, because it's not safe to drink from streams here.  ' 'You are right, my water is dirty also but I am willing to let you have all three water. I would rather eat, so I would like 2 food.' 'Well, if I have to catch fish to eat, I'll need the firewood to cook them.'
Utterance: 'ok, so what at I get 2 firewood and you get 1 so you can cook your fish.'
Example Output:
No