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: Hi. 
 agent: Hello. How can I assist you? 
 customer: I am Emma Young. I am planning to book a ticket from CLT to DFW. Can you please help me out? 
 agent: Ok, may I know your travelling dates? 
 customer: I would like to travel on Mar 10 and return back on Mar 12. 
 agent: Here is a connecting flight with flight number 1029 and fare is 100, providing ticket in economy class. Shall I proceed with booking? 
 customer: That's fine, please proceed the booking. 
 agent: Your booking is done in Spirit airlines. 
 customer: Thank you for your service. 
 agent: Thank you for choosing us.

Ex Output:
book


Ex Input:
customer: Hello. 
 agent: Hello, how can I aid you? 
 customer: I am Stephen Adams. Can you please help me to change my reservation? 
 agent: Sure, please wait. 
 customer: Ok. 
 agent: There is no reservation found with your name. 
 customer: Ok, no problem. Thank you. 
 agent: Have a good day.

Ex Output:
no_reservation


Ex Input:
customer: Hello. 
 agent: Hello. 
 customer: I am Carolyn Mitchell. 
 agent: How may I assist you? 
 customer: Owing to an emergency, I want to cancel my recent reservation. Can you help me out? 
 agent: Please hold on a moment. 
 customer: Ok, take your time. 
 agent: Thanks for your time, there is no reservation found on your name to cancel it. 
 customer: That's ok. Anyways, thank you. 
 agent: Thanks for contacting us.

Ex Output:
no_reservation