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:       Good morning , Sue .  
 Person2:Good morning , Tom.How are you ?  
 Person1:        I'm fine , thanks , how about yourself ?  
 Person2:Things couldn't be better.Where are you going now ?  
 Person1:        I am heading for the library . I've got a research project to do.How about you ?  
 Person2:I'm going to the English class.It ' ll start in five minutes , I've got to run .  
 Person1:        See you later , alligator .  
 Person2:After a while , crocodile . 

formal