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:       Hi , Lilly , it ’ s so nice to see you again . 
 Person2:Hum , me too . This winter holiday was especially long . What have you done ? 
 Person1:        Nothing special . I had a get-together with some schoolmates at the high school , visited the Internet and read a couple of books which I had been longing for . How about yours ? 
 Person2:You know , I like traveling . I made good use of this long vacation and enjoyed myself . 

formal