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 Mike . I forgot about registration . I'm a day late , so all the classes are mostly full . What do you think I should do ? 
 Person2:You're screwed . You can't do anything about that . You have to hope that you get some classes that will be useful . 
 Person1:        Do you think going to the registration building will help at all ? 
 Person2:No . They will tell you the same thing in a worse way . 
 Person1:        Did you register yet ? 
 Person2:Of course . Registering for classes is not something you want to miss . 
 Person1:        What classes do you think are still open ? 
 Person2:Well , I know psychology 101 is a big class , so there will always be seats in that class . You can also get into Sociology . 
 Person1:        That's helpful . Thanks . But what do you think about philosophy . I wanted to take that class this semester . 
 Person2:I took that class last year . The professor is really cool , so if you go to his office , you can have him sign a card that will let you in even if the class is full . 
 Person1:        He does that ? 
 Person2:I guess that's because so many people drop out of that class . 
 Person1:        That makes sense . I think I'll do that . Thanks for all the help . 
 Person2:No problem , man . 

informal