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: 'Looks like we both really need the food.  If you get 2 food I would need 1 food, 2 water and 3 firewood. ' 'Since you will get all the fire would do you think I could have 2 foods and 2 waters. You would get 1 food, 1 water, and 3 firewood. 🙂 You seem like you are a great outdoor person that I would think you would be able to catch some fish to cook with the firewood. 🙂' 'No that does work well for me.  If I only have 1 food I need 2 waters and the firewood to make up for the loss of food.'
Utterance: 'What about I have all the food, and you can have everything else? I would think that seems pretty fair.'
Example Output: Yes

Example Input: Context: 'how about i get 1 water, 2 food, and 2 firewood since I'll be here so long? because of my leg i likely won't be able to leave anytime soon' 'What about I give you more food in exchange for you giving me more water? I could give you 2 food and you give me an extra water?' 'unfortunately that doesnt work for me. i am afraid i will not be able to discuss this any further my final offer is i get 2water 2food and 1wood'
Utterance: 'can we meet in the middle? if we cannot come to an agreement we both get nothing and we both lose. i am in dire need of the water to keep my leg from having to be amputated. i have children at home i take care of and i can't live without my leg'
Example Output: Yes

Example Input: Context: 'I have enough food too. Can I take 2 water, 1 firewood and 2 food?' 'How about two water, 1 firewood and 1 food, since we both value water the most?' 'Is that what you want or what you are offering?'
Utterance: 'That's what I'm offering to you, but I think it's a fair deal, so I'd accept it myself, too.'
Example Output:
Yes