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: Hello. 
 agent: Hello, how may I assist you today? 
 customer: I want to change my existing reservation due to my board exams. Can you help me for that one/. 
 agent: Sure, I am here to help you. May I know your name please? 
 customer: Sure, my name is Nicolas Edwards. 
 agent: Please wait for a while. 
 customer: Sure. 
 agent: Sorry to inform you that there is no active reservation found on your given name. 
 customer: No issues, thank you for the information. 
 agent: Thanks for contacting us.

Output: no_reservation


Input: Consider Input: customer: Hi. 
 agent: Hello. 
 customer: Laura Turner here. 
 agent: How may I aid you? 
 customer: Can you book a flight ticket for my airport codes that is from IAH to IAD? 
 agent: Ok, please mention your dates of travel. 
 customer: The travel dates are from Jan 03 to Jan 05. 
 agent: Do you have any other requirements? 
 customer: I would like to prefer a flight with a stopover option. 
 agent: There is a connecting flight-1009 in economy class, is it fine for you? 
 customer: You can book the flight ticket. 
 agent: Ok, booking is done on Delta airlines. 
 customer: Thank you. 
 agent: Welcome.

Output: book


Input: Consider Input: customer: Hello. I am Stephanie Carter. 
 agent: Hello. How can I help you? 
 customer: I want to travel from DCA to DEN, can you please help me to find a flight? 
 agent: Sure, can you please provide your travelling dates? 
 customer: My travel dates are 09/09 and 09/11. 
 agent: Do you have any other specifications? 
 customer: Yes, connection must be 0 and price 500. 
 agent: Sorry as per your requested dates there is no flight available with 0 connection limit. 
 customer: It's ok. Thanks for your help. 
 agent: You are welcome.
Output: no_flight