Detailed Instructions: In this task, you are given a conversation between a flight agent and the customer. You are given 4 options and you need to select the goal of the conversation. It is provided as part of customer's context, which has to be one of the following: `book`: Make a new reservation, `cancel`: Cancel an existing reservation, `no_flight`: No flight found for the customer's preference, `no_reservation`: No reservation / No change / No cancellation was made in the conversation, mostly enquiring details
Q: customer: Hi. 
 agent: Hello, how may I help you? 
 customer: Please help me to book  a flight ticket from CLT to IAH. 
 agent: Sure, let me know your travel dates please? 
 customer: My trip dates are from Mar, 17 to Mar, 19. 
 agent: Ok, is there any class preference? 
 customer: No. 
 agent: Do you have any time concern? 
 customer: No, I do not have time preferences. 
 agent: Do you need any airline preference? 
 customer: I am happy with an airline. 
 agent: May I know your connection limit? 
 customer: I need a single connecting flight. 
 agent: Can I know your name please to proceed further? 
 customer: Nicholas Robinson. 
 agent: United Airlines is providing connecting flight with the ticket fare of 200 and depart time is 19:00 hours, arrival time is 16:00 hours, Shall I proceed? 
 customer: Please proceed. 
 agent: Your ticket has been confirmed by flight number 1005 and an economy class. 
 customer: Thank you for booking. 
 agent: Thanks for choosing us.
A:
book