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: Hi. 
 agent: Hello. How can I assist you? 
 customer: Due to some issues, I am willing to change my existing reservation. Can you please help me for this? 
 agent: Sure, can I know your name please? 
 customer: I am Rebecca Lee. 
 agent: Ok, wait a moment please. 
 customer: Sure. 
 agent: Sorry, there is no reservation found on your name. 
 customer: Oh! It may not be booked properly due to some technical issues while booking. Thank you for checking. 
 agent: Thank you for approaching us.

Output: no_reservation


Input: Consider Input: customer: Hello. Frank Edwards here. 
 agent: Hello Frank, how may I aid you? 
 customer: Due to an emergency, I want to cancel my reservation. Can you please help me for that? 
 agent: Sure, wait a moment to check your previous reservation status. 
 customer: Ok. 
 agent: Sorry Frank, we don't found any reservation under your name. Would you like to ask us anything else? 
 customer: Nothing, thank you for the information. 
 agent: Ok, thank you for reaching us, have a nice day.

Output: no_reservation


Input: Consider Input: customer: Hello, I am Susan Thompson. 
 agent: Hello, how may I assist you? 
 customer: I want to visit 16th street mall at Denver, please book a connecting flight. 
 agent: Sure, may I know your price limit to book a ticket? 
 customer: I need the ticket within price 500. 
 agent: Ok, what dates you would like to travel? 
 customer: I want to fly on 12/28 and return on 12/30. 
 agent: May I know your airport codes? 
 customer: My origin airport code is TX- DFW and Dest airport code is CO- DEN. 
 agent: Ok, there is a flight 1004 in Southwest airline matching your requirements with price 300. Shall I proceed with this airline? 
 customer: Please proceed with booking. 
 agent: Ok, your ticket has been booked. 
 customer: Thank you for the reservation. 
 agent: Thanks for reaching us. Have a safe journey!.
Output: book