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:       Do you want a cigarette ? 
 Person2:No , thank you . I've given up , you know . 
 Person1:        You don't mind if I have one . 
 Person2:Well , all tight . But you know , smoking does do harm to your health . 
 Person1:        Yes , you are right . 
 Person2:Why don't you try and give it up ? 
 Person1:        I've tried to give up smoking several times , but it's no use . 

formal