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: Consider Input: Person1: How do you like waltz ?
Person2:It's very nice , I like it very much .
Person1: May I invite you for the first dance ?
Person2:My pleasure . But I'm afraid I'm not much of a dancer .
Person1: In fact , I took up dancing quite recently , too .
Person2:Oh , really ? But you're doing the tango wonderfully well .
Person1: I'm glad you say so , you dance beautifully too . It's lucky that I got a partner .
Person2:Thank you for your compliments . It's just that you are a good leader . Do you like the samba and waltz ?
Person1: Yes . And what dances do you like best ?
Person2:Waltz is my favorite . I like it better than any other dances .
Person1: Oh , the music has stopped . Thank you for the dance .
Person2:My pleasure . Let's go and have a drink .
Person1: Fine .

Output: informal

Input: Consider Input: Person1: Hello , is this People's Theater ?
Person2:Yes , it is . May I help you ?
Person1: Yes , are advance tickets for ' Nut croakers ' still available ?
Person2:What date , sir ?
Person1: October 16th .
Person2:Let me see . Yes , we still have some tickets left . Which performance ?
Person1: 7:30 p . m . performance , please .
Person2:OK , we have tickets at 100 yuan and 50 yuan .
Person1: I'd like to reserve two seats at 100 yuan , please .
Person2:All right . May I have you name , please ?
Person1: Du Kun .
Person2:When would you like to collect the tickets ?
Person1: Tomorrow .
Person2:We can hold them until one day before the show .
Person1: How do we cancel , just in case ?
Person2:Just telephone us , and let us know in advance . We don't charge for cancellation .
Person1: All right , thank you very much . Good bye .
Person2:You are welcome . Goodbye .

Output: informal

Input: Consider Input: Person1: Are you feeling OK ?
Person2:My stomach is bothering me .
Person1: What have you been eating ?
Person2:I had a ham sandwich with mayonnaise for lunch .
Person1: Maybe the food had something wrong with it .
Person2:It could be bad food , but I didn ' t feel so well yesterday , either .
Person1: Have you been under a lot of pressure lately ?
Person2:I haven ' t been under any more stress than usual .
Person1: Perhaps you have caught that bug that is going around .
Person2:I feel like maybe I am coming down with the flu .
Output: informal