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? 
 customer: I am Stephanie Harris. As my cultural fest was postponed, I want to change my existing reservation. Could you please help me? 
 agent: Ok Harris, I will be back with your details. 
 customer: Ok. 
 agent: No reservation found with your details. Thank you Harris, have a nice day. 
 customer: No problem, Thank you for your information.
Example Output: no_reservation

Example Input: customer: Hello, I am James Phillips. 
 agent: Hello, how may I serve you today? 
 customer: I have a meeting with my office heads at Benaroya hall on  which is at Seattle. Please help me in booking from IAH to SEA? 
 agent: Sure, can you please share your budget for ticket? 
 customer: I can bare only 200. 
 agent: Do you need any layby in between journey? 
 customer: I need a direct flight. 
 agent: Please specify your assign dates of travelling? 
 customer: My journey dates are 10/17 to 10/19. 
 agent: Ok, please wait a moment. 
 customer: Ok. 
 agent: Thank you for your time, sorry, no flights available on that day. 
 customer: Ok, no issues. Thank you for your help. 
 agent: Thank you for reaching us.
Example Output: no_flight

Example Input: customer: Hello. 
 agent: Hello, how can I guide you for today? 
 customer: I have planned to attend my office meeting in  DEN from EWR, can you assist me in booking my ticket? 
 agent: I am happy to help you in booking your flight ticket. Can you please let me know your planned dates of journey? 
 customer: My trip dates are Oct 27th and Oct 29th. 
 agent: Would you like to have a connecting flight or a direct flight for your journey? 
 customer: Yes, I need one connection between my trip. 
 agent: Can you please let me know your name for reservation purpose? 
 customer: Melissa Carter. 
 agent: Do you have any other specification for your journey to met with? 
 customer: No. 
 agent: JetBlue airlines is providing a flight to your region having a ticket fare of 200 with single connecting flight which departures in the evening. Shall I proceed with the booking in this flight? 
 customer: Proceed. 
 agent: I have booked your flight ticket with the flight 1015 in an economy class. 
 customer: Thank you for booking. 
 agent: You are welcome, thank you for employing our service. Have a safe journey.
Example Output:
book