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.

Ex Input:
Context: 'We cannot budge at all on food. But are more then happy to give up all the extra fire wood for all the food. ' 'Could you trade one food item for either one firewood or water?' 'How about this- You will get 1 food, 1 water and 3 Firewood. I will get 2 Food and 2 Water with 0 Firewood. '
Utterance: 'Hmm, I think I would prefer your original offer instead. You can have all the food if I can have all the rest.'

Ex Output:
No

Ex Input:
Context: 'Hey, I was thinking that I could take all of the food items, and 2 of the firewood items. My friend has low blood sugar and they need the food in case they crash, and the warmth of the fire to maintain at evening.' 'Water is my highest priority, what is yours? Is it food?' 'Yes, food is my highest. It's necessary for my friend to keep extra around just in case he crashes. Why is water your highest priority?'
Utterance: 'I need the water to drink - I don't trust the water I might find at the campsite.'

Ex Output:
No

Ex Input:
Context: 'you told me i not fair that why i told you are not fare,3 food for me will give 3 firewood for me, give 2 water for me, other we can end the deal and both we can forget the bonus' 'ok' 'then what will do ? if you ok for 3 food for me , 3 firefor you, 2 water for me , for this deal we can go forward?'
Utterance: 'of course not. you just took all the priority items and you still want two water. I am going to make the last offer. you take two food and two water, I take one food, three wood and aone water. '

Ex Output:
Yes