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'll need water. My kids take medications and need to stay hydrated.' 'Absolutely. My second most needed item is food so that works out well.' 'Well I am happy to give you all my food in exchange for all your water.'
Utterance: 'We can do that! How do you want to split up the firewood?'
Example Output: No

Example Input: Context: 'I have a medical condition that causes my veins to close up when I get too cold. I will thus need the 3 firewood.' '☹️Oh, that sounds awful. Are you sure you need all three packages of firewood?'
Utterance: 'I might be able to get by with just two... I'm on a diet though, so I don't need as much food.'
Example Output: No

Example Input: Context: 'Hello - I would love be able to split some supplies with you🙂. I could use some extra firewood so maybe i could take 3 and maybe you could have some extra food? ' 'Maybe I could take 2 firewood 2 food and 0 waters?'
Utterance: 'I was planning on staying up all night and keeping my fire going all night. Honestly I could give you all the extra food if that helps you if I could please have the 3 firewood? We could split the waters'
Example Output:
No