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 don't think we come here at a right time .  
 Person2:What's wrong ?  
 Person1:        The museum doesn't open today .  
 Person2:What a pity !  
 Person1:        Where shall we go now ?  
 Person2:Why not have a visit to the zoo ? 
Output:
informal