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 , what's the price of a single room ?  
 Person2:That's $ 50 for a single night .  
 Person1:        Are meals included ?  
 Person2:Yes , of course . Can I make a reservation for you ?  
 Person1:        Fine , I want to book one for overnight . 

formal