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:     Excuse me , sir . I wonder if I could exchange the shoes for a larger one .  
 Person2:  No problem . May I see your receipt , please ?  
 Person1:      Here you are .  
 Person2:  That's right . Now try on this one . It's size 41 . 

0