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'.

Example Input: Person1: I've brought a little dog for Alice , girls usually like looking after pets .
Person2:Thank you , but Alice is only a visitor here . I don't know if she'll keep it .
Person1: To tell you the truth , the dog isn't my real reason for coming . I want to ask Alice if she'd like to be my girlfriend .
Person2:Really ?
Example Output: informal

Example Input: Person1: Good afternoon , everyone . The experiment is to start at 3 . Have you gone through the instructions ?
Person2:Yes , sir .
Person1: Ok , now some points for attention . First of all , pay attention to safety ... Now , sign your names on the lab record , and after that you can start . If there is any question , just let me know .
Person2:Excuse me , sir . This air compressor doesn't work .
Person1: Have you turned it on ?
Person2:Yes , I have .
Person1: Ok , I will get you another one .
Person2:Thank you .
Example Output: formal

Example Input: Person1: If I remember correctly , time of delivery is another point on wich we differ .
Person2:That's right . Let's go into the details .
Person1: Ok . I hope you can have these goods delivered before the end of Sep . We'd like them to be there in time for our Christmas sales .
Person2:Christmas doesn't come until almost the end of the year , right ?
Person1: But in the United States the Christmas season begins about a month before Dec . 25 .
Person2:Well . I am afraid it will be difficult for us to advance the time of shipment . Our manufacturers are fully committed at the moment .
Person1: I hope you'll try to get them to step up production .
Person2:As new orders keep pouring in , the workers are working three shifts to step up production .
Person1: If that's the case , there is nothing more to be said .
Person2:I am sorry .
Person1: What's your last word as to the date then ?
Person2:I said by the middle of Oct . This is the best we can promise .
Person1: All right . I'll take you at your word .
Person2:Good . Let's call it a deal . We will do our best to advance the shipment , but your L / C should be opened early Sep .
Person1: I promise .
Example Output:
informal