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:       What are you doing this Saturday ?  
 Person2:Not much .  
 Person1:        Do you want to go see a movie ?  
 Person2:That sounds good .  
 Person1:        What's playing at the Century Fox ?  
 Person2:Candlelight in the Window  
 Person1:        Should we go see it ?  
 Person2:I'd rather not . I don't like horror movies .  
 Person1:        How about ‘ Run of the Mill ? ’  
 Person2:No . I heard that's really boring .  
 Person1:        Why don't we go to a concert instead ?  
 Person2:Great idea ! 

informal