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:       Excuse me , but could you give me some change ?  
 Person2:Let me see . Are dimes and quarters OK ?  
 Person1:        I want to make a long distance phone call .  
 Person2:Then you'll need small change . 

formal