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:       Is there anything I can do for you ?  
 Person2:I want to have a trip to Sydney .  
 Person1:        Sure . How long is your vacation ?  
 Person2:3 weeks  
 Person1:        Well , how do you like this one ? You will stay there for 17 days .  
 Person2:It's good . By the way , what kind of clothes do I have to bring with me ?  
 Person1:        It's summer in Sydney so you have to bring your summer wear . 

formal