Definition: You are given a conversation between two people. 'Person1:' and 'Person2:' are used to separate their respective dialogues. If the conversation begins with a question, label it '1' otherwise '0'.
Input:  Person1:     Lily , do you know Lizzy ? 
 Person2:  Lizzy who ? 
 Person1:      Lizzy smith . 
 Person2:  Of course I do . 
 Person1:      Then , Do you know her younger sister ? 
 Person2:  You mean Mary ? 
 Person1:      Yes . 
 Person2:  Sure . I know her elder sister Sue and younger sister Mary . 
 Person1:      Oh , not bad . Then do you know her mother ? 
 Person2:  Yes , certainly . I know her mother and father , and brother and sisters , too . 
 Person1:      That sounds terrific . 
 Person2:  Why do you ask me these questions ? 
 Person1:      I just want to visit the family some day . 

1