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:       Fair-Priced Fares , how may I help you ? 
 Person2:How much is a round-trip ticket to London ? 
 Person1:        When did you plan to go , sir ? 
 Person2:In the second week of September . 
 Person1:        The second week of September is still in the high-season , so the cheapest tickets are $ 650 . The high season lasts until the 15th , so fares after that date are cheaper . 
 Person2:In that case , I'll go after the 15th . How much are the off-season fares ? 
 Person1:        Our cheapest ticket is $ 550 on American Airlines . 
 Person2:Okay , I'll take it . ( to be continued ) 

formal