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:       Something's wrong with my computer .  
 Person2:Exactly what ?  
 Person1:        All I get is a black screen .  
 Person2:What's the matter ?  
 Person1:        I think I know , because this happened before .  
 Person2:What happened before ?  
 Person1:        My hard drive crashed .  
 Person2:Oh , no . That's bad news .  
 Person1:        It sure is , but I'm going to call HP first , just to make sure .  
 Person2:Will you lose all your files ?  
 Person1:        No , I always back up my files .  
 Person2:You're smart . 

informal