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 , John .  
 Person2:Good evening , Mary .  
 Person1:        How are you doing ?  
 Person2:I'm doing fine , thanks.What ' s new with you ?  
 Person1:        Nothing special .  
 Person2:I'm wondering whether you could come over for a pizza sometime next week ?  
 Person1:        Sounds good.Sorry , here comes my bus.You call me , or I'll call you to make a date .  
 Person2:I'll call you .  
 Person1:        All right.Gotta go , bye , keep in touch .  
 Person2:Have a great day , take care , bye . 

informal