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 , ma'ma ?  
 Person2:Please , where do I catch the plane for New York ?  
 Person1:        First you must check in at Counter No . 4 .  
 Person2:That one there ?  
 Person1:        That's right . Then you will follow the signs to Gate 85 .  
 Person2:Thank you . You ' Ve been very helpful . 

informal