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:       You mustn't touch the wet paint , Bill .  
 Person2:I'm sorry . I won't do it again .  
 Person1:        Try to be more careful in future .  
 Person2:I shall . I wasn't as careless as John Sampson . He walked across that wet cement over there .  
 Person1:        The workmen oughtn't to leave it without a no tice .  
 Person2:The headmaster asked them not to do so .  
 Person1:        Then why isn't there a notice ?  
 Person2:They went to their stores to get one . Here they come with it now !  
 Person1:        But look at them ! They've forgotten about the wet cement and they're walking across it to put up the notice ! 

formal