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: 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 !
Example Output: informal

Example Input: Person1: Oh , what a pleasant surprise ! Don't you remember me ?
Person2:Mr.Black , if I'm not mistaken .
Person1: Right ! Glad to see you here .
Person2:Pleased to see you.too .
Example Output: informal

Example Input: Person1: I may go grocery shopping later .
Person2:We need to get food ?
Person1: I don't think we have any food .
Person2:What are you going to buy ?
Person1: What food are we out of ?
Person2:Go and look in the kitchen .
Person1: Could you look for me ?
Person2:You should just get the basics .
Person1: What would that be ?
Person2:Get some eggs , milk , and bread .
Person1: Would you please make a list for me ?
Person2:Okay , I'll write it down for you .
Example Output:
formal