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

Example Input: customer: Hello. 
 agent: Hello, how can I help you today? 
 customer: Can you please change my existing reservation? 
 agent: Sure, we are here to help you. May I know your name? 
 customer: Sure, I am Helen Wilson. 
 agent: Ok , wait for some time. 
 customer: Sure. 
 agent: Thanks for waiting there is no reservation found on your name. Thanks for approaching us.
Example Output: no_reservation

Example Input: customer: Hello,. I am Susan Gonzalez. 
 agent: Hello, how can I help you? 
 customer: I need to book a flight ticket from Seattle to meet my grandparents after a long time in Washington. Can you please help me in booking? 
 agent: Sure, may I know your planned travel dates? 
 customer: My depart is on 03/17 and arrival on 03/19. 
 agent: Please share me your source and destination codes. 
 customer: My source code is WA-SEA and destination code is DC-IAD. 
 agent: May I know your price limit? 
 customer: I can spend up to 5000. 
 agent: Please wait for a moment. 
 customer: Ok. 
 agent: Thanks for waiting, sorry to say that, no flights were found with your details. 
 customer: Ok, no issue. 
 agent: Thank you for opting us. 
 customer: Thank you for your support.
Example Output: no_flight

Example Input: customer: Hello. 
 agent: Hello, how can I help you today? 
 customer: Can you please help me to book a flight ticket from ORD to SEA? 
 agent: Sure, please share your planned travel dates? 
 customer: My trip dates are Apr 10 to Apr 12. 
 agent: Any other requirements to be met? 
 customer: No. 
 agent: Can I have your name please? 
 customer: My name is Shirley Hall. 
 agent: Frontier Airline flight 1003 available with connection limit 0 and fare is 200, shall I confirm this economy class flight? 
 customer: Ok, please proceed. 
 agent: Ok, your ticket has been booked. 
 customer: Thank you. 
 agent: Thank you for reaching us.
Example Output:
book