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:       What are you doing tonight ?  
 Person2:I have to run to the grocery store .  
 Person1:        Don't you hate fighting the crowds on the weekends ?  
 Person2:Yes , but I am out of food and milk .  
 Person1:        What store do you shop at ?  
 Person2:The small one , just down the street . I like their generic brand .  
 Person1:        I have been using the store across town for years .  
 Person2:I hear they have very nice stuff .  
 Person1:        They do , but they're a little expensive on certain items .  
 Person2:Well , you should try my store . The prices are good .  
 Person1:        I will sometime . Thanks for the advice . 

informal