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:       Do you have spare time tonight ? 
 Person2:What's the matter ? 
 Person1:        There will be a live show of football tonight . 
 Person2:What teams are playing tonight ? 
 Person1:        AC Milan versus Real Madrid . 
 Person2:That will be a tough match , right ? 
 Person1:        Absolutely . 
 Person2:What are we waiting for ? It's already 7 pm now . Let's buy some drinks and desserts now . 
 Person1:        Great idea ! Here we go ! 

informal