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:       Hello , Jill . 
 Person2:Tom , You're back , come in please.How are you ? 
 Person1:        Fine , only a little tired . 
 Person2:You'll recover after a good night's sleep . 
 Person1:        Thank you very much for looking after my house in my absence . 
 Person2:That's all right.Would you have a cup of coffee ? 
 Person1:        Yes , Please.It ' s very kind of you . 
 Person2:Don't mention it . 
 Person1:        The rooms are very tidy and the flowers grew very well.You are very helpful . I want to thank you for everything you've done for me . 
 Person2:It's my pleasure . 
 Person1:        I bought you some books on literature , I don't know if you would like them . 
 Person2:Thank you.Thank you for the trouble you've taken . 
 Person1:        Not at all . 

informal