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:       Good evening.Welcome to our program . 
 Person2:Thank you.Good evening , Mr.Dean . 
 Person1:        Would you tell us your name , please ? 
 Person2:I'm Helen Baker . 
 Person1:        Glad to meet you , Ms.Baker . 
 Person2:Glad to meet you , too . 
 Person1:        Where are you from , Ms.Baker ? 
 Person2:I'm from New Zealand . 
 Person1:        What do you do for a living ? 
 Person2:I'm a teacher . 
 Person1:        Thank you for coming , Ms.baker . 

informal