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

Ex Input:
customer: Hello. 
 agent: Hello, what can I do for you today? 
 customer: My name is Karen Hill and I want to book the flight ticket from LAS to EWR. Can you please help me? 
 agent: Sure, may I know your travel dates? 
 customer: My travel dates are May 17 and May 19. 
 agent: Let me know your class preference? 
 customer: I am comfortable with any class. 
 agent: Do you have any other requirements to be met? 
 customer: I need a single connection flight. 
 agent: Sorry, no flights found on your travel dates. 
 customer: Ok, thank you for the information. 
 agent: Thank you for contacting us.

Ex Output:
no_flight


Ex Input:
customer: Hello, Stephanie Carter here. 
 agent: Hello Stephanie, how may I assist you? 
 customer: I want to visit PHL. Can you please book my ticket from EWR? 
 agent: Sure, let me know your travelling dates please. 
 customer: My trip dates are 09/09 and 09/11. Please make sure this flight have minimum 1 connection. 
 agent: I am sorry, there is no flight available with 1 connection. 
 customer: Ok. Thank you. 
 agent: You are welcome.

Ex Output:
no_flight


Ex Input:
customer: Hello, I am Larry Hall. 
 agent: Hello, how may I assist you? 
 customer: Can you make a reservation from SFO to EWR? 
 agent: Sure, may I know your travel dates please? 
 customer: I am planning to start on 04/26 and return back on 04/28. Make sure that price limit is 200. 
 agent: Ok, hold on for a moment. Let me check the best flight for you. 
 customer: Ok. 
 agent: I found a flight for you with Hawaiian airline and it costs you 200. Shall I proceed? 
 customer: Yes, you can go ahead if it's connection limit is 1. 
 agent: Your ticket has been booked with 1004 flight number. 
 customer: Thank you. 
 agent: Welcome, thank you for choosing us. Have a safe flight. 
 customer: You are welcome.

Ex Output:
book