Definition: You are given a conversation between two people. 'Person1:' and 'Person2:' are used to separate their respective dialogues. You are required to assign a label 'formal' if there is an absence of emotion and a presence of questions anywhere within the conversation. If such pattern is not found assign the label 'informal'.
Input:  Person1:       Hey , let's eat out tonight .  
 Person2:What's the occasion ? You won the lottery ?  
 Person1:        No . Just want to relax a little bit . You don't have to win the lottery to relax , do you ?  
 Person2:Well , I am kind of broke .  
 Person1:        Come on . It's on me .  
 Person2:Really ? It's very nice of you .  
 Person1:        Don't be silly . I'll take you anywhere you wanna go .  
 Person2:Wonderful ! You know what ? I wish you wanted to relax everyday .  
 Person1:        Dream on ! 

informal