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:       May I help you ?  
 Person2:Yes , could you cash these travaler's check for me , please ?  
 Person1:        Sure.Please sign your name here ... and here .  
 Person2:Ok , here you are .  
 Person1:        Thanks.How would you like them ?  
 Person2:It doesn't matter . 

formal