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's your email address ?  
 Person2:It's bulldog 123 .  
 Person1:        Bulldog 123 . Are you sure that's all ?  
 Person2:Yes .  
 Person1:        No . That's incomplete .  
 Person2:What do you mean ?  
 Person1:        What's your mailing address ?  
 Person2:456 Cherry Drive , Pasadena , CA 91170 .  
 Person1:        That's correct .  
 Person2:So what's the problem ?  
 Person1:        Bulldog 123 is just the street . You have to give me the city , state , and ZIP code .  
 Person2:Oh , I get it . My email address is bluedog123@yahoo.com . 

formal