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. 
 customer: I am Barbara Green. 
 agent: How can I assist you? 
 customer: I am very interested in Hiking and cycling. So, I am willing to visit Hiking and cycling at Bear Mountains. Can you please help me to reserve a flight ticket for me from PHX to LAX? 
 agent: Sure, may I know your preferred journey dates? 
 customer: Sure, I have planned my journey dates on 02/03 and I will catch the return flight on 02/05. 
 agent: Please give me a minute. 
 customer: Sure, take your own time. 
 agent: I found a flight for you in UA airlines with price 200. Shall I book the ticket for you? 
 customer: I am ok with the flight that you have provided to my journey. Continue with flight ticket booking. 
 agent: Your ticket is confirmed and the flight number is 1002. 
 customer: Thank you for your help in my flight ticket booking. 
 agent: Thank you for contacting us, have a safe journey. 
 customer: You are welcome.
Example Output: book

Example Input: customer: Hello, I am David King. 
 agent: Hello, how may I help you? 
 customer: As my manager did not approve my leave, I would like to change my reservation. 
 agent: Sure. Please let me a moment. 
 customer: Ok, take your time. 
 agent: Sorry, there is no reservation found on your name. 
 customer: That's ok, thank you for checking. 
 agent: Welcome. Thank you for reaching us. 
 customer: Welcome.
Example Output: no_reservation

Example Input: customer: Hello. 
 agent: Hello. 
 customer: I am Rachel Thompson. 
 agent: How may I help you? 
 customer: I want to change my existing reservation, due to my family tour got postponed. Could you help me in changing reservation? 
 agent: Sure. Please wait a moment, I will check for the reservation with your name. 
 customer: Ok. 
 agent: Thanks for your time, there was no reservation found on your name. 
 customer: Not an issue. 
 agent: Thank you for reaching us. 
 customer: Thanks for your service.
Example Output:
no_reservation