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:       what do you think about all the different diets people go on ? 
 Person2:I don't think dieting is good for you . It's much better to eat a balanced diet and to never get overweight to begin with ! 
 Person1:        but what do you think about people who are obese ? What should they do to lose weight ? 
 Person2:they need to eat healthy foods , but they also have to increase the amount of exercise they do every day . They don't have to cut out fattening foods altogether , though . 
 Person1:        so you think it's ok for people who are dieting to eat chocolate ? 
 Person2:sure , they can eat some chocolate . As long as they are exercising and eating mostly healthy foods , there's nothing wrong with having a small desert . 
 Person1:        how about drinking soda ? 
 Person2:many people gain weight by drinking far too much soda . Soda should be a treat ; there's simply no nutritional value in it whatsoever . If you want to lose weight and you can't stop drinking soda , try 
 Person1:        that's good advice . Have you ever tried taking vitamins ? 
 Person2:my mother used to make me take vitamins every day , but I don't take them anymore . Vitamins are good as a supplement , but they don't do much good if you don't have a well-balanced diet to start . 
 Person1:        how do you know so much about food and dieting ? 
 Person2:you might not believe this , but I used to be twice the size than I am now ! 

formal