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'.

Ex 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 .

Ex Output:
formal

Ex Input:
Person1: Excuse me , Sir , do you know what time it is ?
Person2:Oh , it ' s almost eleven twenty .
Person1: Thank you .
Person2:You ' re welcome . The rain is quite heavy , isn ' t it ?
Person1: Yeah . I was in a hurry and I forgot my umbrella today .
Person2:I have one . We could share it . Which way are you going ?
Person1: Oh , that ' s very kind of you . I am going to the Garden Hotel .
Person2:I am going there , too . We can walk together .
Person1: Sure .

Ex Output:
formal

Ex Input:
Person1: Would you please teach me how to use the computer ?
Person2:Sure , let's take a look at the menu first .
Person1: Do I have to turn on the computer ?
Person2:yes , we can look at the computer and computer menu at the same time . And this will help us understand both better .
Person1: What should I learn first ?
Person2:Right now I'll teach you to open files , save files and copy files . Are you ready ?
Person1: I am ready I am going to get , let's start !

Ex Output:
informal