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:       Mike's going to have a self-driving traveling across the country . 
 Person2:Really ? He is so great . 
 Person1:        You don't want to join him ? 
 Person2:Surely I want . It's quite popular nowadays . 
 Person1:        Yes , and I want to have a try . 

informal