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:       Hi charles , I want you know that i finally found an apartment in haitian .  
 Person2:You did ? that is great !  
 Person1:        Yeah , I am having a party this saturday night , a sort of house warming , and i want to invite you . are you busy ?  
 Person2:No i am free , i will be there , what time the thing starting ?  
 Person1:        Around seven .  
 Person2:Ok , great , should i bring anything ?  
 Person1:        No , but thanks for offering , actually could you bring some fold-up chairs for people if you have any ? I am afraid not everyone's going to have a seat , do you have any ?  
 Person2:sure , I will be happy to bring a few , what is the address ?  
 Person1:        Don't worry , I will come to pick you up at about six thirty .  
 Person2:Got it . 

informal