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

Input: Consider Input: customer: Hello, my name is Katherine Miller. 
 agent: Hello, Katherine Miller. How can I assist you? 
 customer: I am planning to spend my vacation holidays with my brother, so I need to make a flight reservation. 
 agent: OK, what is your exact destination and when do you want to go? 
 customer: My destination airport is PA-PHL, and my travelling dates are departure on 03/20 and arrival on 03/22. 
 agent: Let me know your source point. 
 customer: My source airport is San Francisco, CA-SFO. 
 agent: Sorry to inform, no flights are found regarding to your specifications. 
 customer: That's not a problem, thanks for your information. 
 agent: Thanks for choosing us. Have a great day.

Output: no_flight


Input: Consider Input: customer: Hello, I am Betty Campbell. 
 agent:  Hello, How exactly I can serve you the best today? 
 customer: Can you help me to book a direct flight from LGA - OAK? 
 agent: Sure, I will help you with that. 
 customer: Thanks. 
 agent: Kindly, mention your travelling dates? 
 customer: My travelling dates are 07/26 and 07/28. 
 agent:  Ok, please wait a moment, let me search a flight for you. 
 customer: Sure. 
 agent: Sorry to inform you, currently no flights are running at that locations due to abnormal weather conditions. 
 customer: Ok, no issues. Thank you. 
 agent: Thank you for choosing us.

Output: no_flight


Input: Consider Input: customer: Hello. 
 agent: Hello. How can I assist you today? 
 customer: I want to change my recent reservation. Can you help me out? 
 agent: Can I know your name? 
 customer: I am Jeffrey King. 
 agent: Please wait. 
 customer: Ok, take your time. 
 agent: Sorry, no reservation found on your name to change. 
 customer: That's ok. Anyways, thank you. 
 agent: Most welcome.
Output: no_reservation