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: 'my people feel like they need 1 extra of something or else they will throw a fit ☹️' 'No fits!!  They're getting that extra water they really want.  I am sure they'll be OK with giving a group with kids a little extra firewood to make this camping trip awesome for them' 'Okay if they get 3 water they are good with that allotment for the others'
Utterance: 'I think taking 1 extra water, for safety purposes will be OK for us and your group will get that.  I am going to submit a GREAT offer that is mutually beneficial.  '
Example Output: Yes

Example Input: Context: 'What if I get 2 food packages and 1 water package....and you would get 1 food package and 2 waters?' 'I think we will need more extra food than that.  How about the reverse, I get 2 food and 1 water and you get 1 food and 2 water.' 'I could do that if I could then get 2 packages of wood as well because it's been bitterly cold this time of year at night in the Alleghenies.'
Utterance: 'That sounds fair.  So I would get 2 food, 1 water, and 1 firewood.'
Example Output: Yes

Example Input: Context: 'Terribly sorry to hear that; it sounds like you won't be able to camp much in that condition. I assume you have someone coming along to help you because of your leg?' 'just a bunch of children under 5 who wont be able to gather firewood. so i desperately need at least 2' 'I see, well it sounds like you're going to need some additional food with those children. How about I provide you with some additional food and you can help me with my need for heat with firewood?'
Utterance: 'okay how i take all 3 food and 1 firewood?'
Example Output:
No