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:       it's a lovely day , isn't it ? 
 Person2:yeah , and most excitingly , I met the girl living under me today . She's really nice . 
 Person1:        is she American ? 
 Person2:yeah , and most importantly , she's single ! Man , I could tell from the moment I saw her , she's the girl of my dreams ! 
 Person1:        so I take it you two are hitting it off ? I know it's very convenient to be in a relationship with your neighbor , but what if you break up ? 
 Person2:I don't know . I am not really worried about that . I don't wanna lose before even starting . Besides I think the other two American guys have also fallen for her . 
 Person1:        sounds like you've got some competition . You made a move already ? 
 Person2:not yet . But I am thinking of inviting her to dinner sometime . I know some good restaurants nearby . 
 Person1:        that's nice . Having been here a little while surely gives you the advantage , eh ? 
 Person2:you bet . Now that you mentioned it , I think I'll call her now and see if she is available tonight . 
 Person1:        good luck ! 
 Person2:thanks ! 

informal