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 my hair done yet ? 
 Person2:Yeah , I just need to make the final touches . 
 Person1:        How long until you're finished ? 
 Person2:I'm finished . What do you think ? 
 Person1:        I like my hair so much . 
 Person2:Do you really ? 
 Person1:        It's beautiful . 
 Person2:Well , thank you very much . 
 Person1:        How much is it for my hair ? 
 Person2:You owe me $ 55 . 
 Person1:        Thanks for everything . 
 Person2:You are very welcome . Come back again . 

informal