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 Bobby . What's going on ? 
 Person2:Just taking a smoke break . 
 Person1:        I forgot my cigarette today . Do you have another one ? 
 Person2:Sure . Here you go . 
 Person1:        Thanks . 
 Person2:I didn't know you smoked . 
 Person1:        Really ? I've been smoking for over a year now . 
 Person2:Oh . You're new to smoking still . I've been smoking for 7 years . 
 Person1:        You ever tried to quit ? 
 Person2:Many times . I'm really addicted . It's harder to stop than you think . 
 Person1:        Yeah . I tried to quit last month , and I thought it was going to be easy , but it turns out that I'm still smoking . 
 Person2:I highly recommend you quit soon . The longer you smoke , the harder it becomes to quit . 
 Person1:        I think you're right . Aright . Gotta go to class . Thanks for the cigarette . I'll talk to you later . 
 Person2:No problem . I'll talk to you later . 

informal