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, I am Gregory Johnson. 
 agent: Hello, how may I render you? 
 customer: I want to reach New York, NY - EWR, to meet my cousin on her birthday. 
 agent: Ok. 
 customer: Can you help me with reserving a flight ticket within range 1000? 
 agent: Sure, we are pleased to serve you. May I know your boarding point? 
 customer: I want to board from Austin, TX - AUS. 
 agent: When did you planned to travel? 
 customer: I have planned to travel on 02/12 and return on 12/14. 
 agent: Please wait for a while. 
 customer: Sure. 
 agent: Thank you for waiting, we are sorry to inform you that no flights were available based on your schedule. 
 customer: Ok, not a problem. Thanks for your kind help. 
 agent: Thank you for reaching us.

Ex Output:
no_flight


Ex Input:
customer: Hello. 
 agent: Hello, how can I assist you for the day? 
 customer: I would like to meet my old friend at Las Vegas, please help me in booking a ticket from IAH to LAS. 
 agent: When you are willing to travel? 
 customer: My planned travel dates are on Mar 11 and Mar 13. 
 agent: Do you have any connection limit? 
 customer: I need a direct flight for this trip. 
 agent: May, I know your good name? 
 customer: My name is Jessica Wilson. 
 agent: Do you have any other specifications? 
 customer: No more specifications, please find the availability of flights. 
 agent: Sorry, we found no flights on your given dates. 
 customer: Ok, no issues. Thank you for your information. 
 agent: Thank you for reaching us.

Ex Output:
no_flight


Ex Input:
customer: Hello. 
 agent: Hello. How may I help you today? 
 customer: Can you please change my existing reservation? 
 agent: Sure, may I know your name for change in the reservation? 
 customer: Sure, I am Sharon Wright. 
 agent: Please wait a moment. 
 customer: Sure. 
 agent: Thank you for waiting. Sorry, there are no active reservations on your name to change. 
 customer: Thank you for your information. 
 agent: Thank you for reaching our service.

Ex Output:
no_reservation