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:       Can we have two tickets for this evening's film ?  
 Person2:Sure.Which one ?  
 Person1:        Titanic .  
 Person2:Where do you want to sit ?  
 Person1:        Front , please .  
 Person2:Are these seats all right ? They're in the second rows .  
 Person1:        Do you have seats in the fourth or fifth rows ?  
 Person2:Sorry.We ' Ve nothing further back .  
 Person1:        All right.We ' ll take the second row.By the way , how much is it ?  
 Person2:Thirty yuan .  
 Person1:        Fairly expensive . 

formal