You will be given a definition of a task first, then some input of the task.
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'.

Person1: Excuse me , sir.You are not supposed to smoke here .
Person2:I beg your pardon ?
Person1: Your seat is in the non-smoking section.So , please refrain from smoking .
Person2:Oh , I see.Since I'm a heavy smoker , may I change my seat ?
Person1: Then , I'll try to find a seat in the smoking section.One moment , please . Thank you for waiting . I found a seat in the smoking section for you .
Person2:Oh , did you ? Thanks a lot .
Output:
informal