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: My name is Stephen Johnson. As my business trip got postponed to other dates, I would like to change my existing reservation. 
 agent: Please wait for a while. 
 customer: Sure. 
 agent: Sorry, there is no reservation found by your name. 
 customer: That's fine. Thank you for your information. 
 agent: Thank you and have a nice day.
Example Output: no_reservation

Example Input: customer: Hello. 
 agent: Hello. How can I help you? 
 customer: I would like to book a ticket from MCO to DEN, can you please help me out? 
 agent: Can I know your travelling dates? 
 customer: I am travelling on these dates April 20th and 22nd. 
 agent: Is there any airline preference? 
 customer: I don't have any preference. 
 agent: Do you have any class preference? 
 customer: I don't have any other preferences. 
 agent: Let me know your name. 
 customer: Janet Phillips here. 
 agent: Connecting flight can be booked with Hawaiian airlines for price 100 having flight number 1000. 
 customer: Ok, you can proceed. 
 agent: Ticket is booked. 
 customer: Thank you for your services. 
 agent: Thank you.
Example Output: book

Example Input: customer: Hi. 
 agent: Hello,. 
 customer: I am Scott Thompson. 
 agent: How can I aid you? 
 customer: I want to book a flight ticket from NY-JFK and its a round trip to attend a housewarming ceremony. 
 agent: Ok, may I know your trip dates? 
 customer: 06/13 and 06/15 are my travelling dates. 
 agent: Do you have any price limit? 
 customer: 200 is my price. 
 agent: Please be on hold I will get back to you with the availability of flights. I found a flight with the number 1001 in an airline AA. Shall I proceed to book? 
 customer: Sure, You can proceed. 
 agent: Your flight ticket has been booked. 
 customer: Thank you. 
 agent: Thank you for choosing us.
Example Output:
book