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:       If you wanna keep healthy , you must give up smoking . It's extremely bad for your health , you know . 
 Person2:I know it's not good for me , but the problem is I just can't help it . 
 Person1:        Well , I've got an idea , put the label cancer sticks on each pack of cigarettes , and read it before you smoke . It may give you a feeling to reduce it . 
 Person2:I'll try . 

informal