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:       I'd love to continue this conversation , but I really need to go now . I have to get back to the office .  
 Person2:Well , let's get together soon .  
 Person1:        Okay . Would you like to have lunch some day next week ?  
 Person2:Sure . How about Monday ?  
 Person1:        Hmm . I'm afraid I can't make it on Monday . I've got to fly to Chicago on business .  
 Person2:Well unfortunately , I'm tied up on Tuesday . I'm supposed to have lunch with an important visitor from out of town , and I don't think there's any way I can get out of it.Are you free on Wednesday ?  
 Person1:        Wednesday ? Let me see . Hmm . Somehow I think I've already got something scheduled for Wednesday . Oh , yes ! I've got an appointment with my dentist to have my teeth cleaned , and it's essential that I keep it .  
 Person2:Well , I'm afraid Thursday is out for me . I'm expected to attend a meeting of our personnel committee , and it's very important for me to be there .  
 Person1:        So that leaves Friday . I don't have any obligations or commitments on Friday.How about you ?  
 Person2:Friday sounds good . Where should we meet ?  
 Person1:        You know , I really must be going now or I'll be very late . Can you give me a call tomorrow an we'll decide ? 

formal