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 stayed online chatting with friends all night . It was great fun .  
 Person2:I don't understand . You don't even know the ' friends ' you are ' talking ' to !  
 Person1:        It is better I don't know them . So I can say anything I want .  
 Person2:Do you believe what they say ?  
 Person1:        Who cares ? It's just online . It's not real . Do you want to join me tonight ?  
 Person2:Thanks , but I'm a lousy typist . 

formal