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 Jack . How were your classes this semester ?  
 Person2:They were not too bad . I really liked my poli-sci class .  
 Person1:        Would you consider it your favorite class ?  
 Person2:I don't know if I would call it my favorite , but it ranks up there .  
 Person1:        What class was your favorite then ?  
 Person2:I took a business communication class last year and it was terrific .  
 Person1:        I never took that yet . If that was your favorite , I think I will check it out . 

formal