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: I've got a complaint about the noise next door .
Person2:Yes , it's most irritating .
Person1: Some people aren't very considerate .
Person2:We're going to do something about it .
Person1: Yes , I think so .
Person2:We can't put up with it any more .
Person1: We'll play the CD loud , is that all right ?
Person2:I don't think so .
Person1: What should we do ?
Person2:Why don't we call them ?
Person1: Good idea .
Output:
formal