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:       Excuse me , miss.Should I check in here for taking MS121 to Florence ?  
 Person2:Yes , show me your ticket and passport please .  
 Person1:        Here you are . Can I have a seat in the back of the plane ?  
 Person2:No problem . Wish you a nice trip . 

formal