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:       Would you like to book a table , sir ?  
 Person2:Yes , would you arrange it for me the day after tomorrow ?  
 Person1:        Sure , when ?  
 Person2:Six o'clock in the afternoon .  
 Person1:        For how many guests , please ?  
 Person2:Six .  
 Person1:        How much would you like to spend ?  
 Person2:We don't care about money . We'd like to have some good dishes of local specialties .  
 Person1:        OK .  
 Person2:How many courses are there altogether , please ?  
 Person1:        Eight .  
 Person2:Could you tell me some of entrees about the dinner ?  
 Person1:        Sure . The main courses are roast Beijing duck and fried eel slices .  
 Person2:Very good . 

informal