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 . 
 Person2:Yes ? 
 Person1:        Do you have any information about the city sights ? 
 Person2:Sure . There ’ s a lot here in this pamphlet . 
 Person1:        Thank you . And what ’ s the best way to get downtown ? 
 Person2:Take the subway . It ’ s $ 1.50 per ride . You can buy a metro card at the station . 
 Person1:        You ’ Ve been very helpful . 
 Person2:My pleasure . 

informal