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 Laura Turner. 
 agent: Hello, How can I serve you? 
 customer: I want to fly with the direct flight from Washington to attend an interview in Philadelphia, can you help me to book an economy class ticket? 
 agent: Sure, May I know the travel dates? 
 customer: I intend to start on Nov 28th and I will return within two days that is on Nov 30th. 
 agent: Please help me with your journey codes. 
 customer: My source and destination airport code are IAD and PHL. 
 agent: Please wait a minute. 
 customer: Sure. 
 agent: Sorry, No flights found with your chosen dates. 
 customer: No issues, I'll choose any alternative to reach my destination. Thank you. 
 agent: Thank you for opting us.

Ex Output:
no_flight


Ex Input:
customer: Hi. 
 agent: Hello. How may I assist you? 
 customer: I am looking for a direct flight from JFK to DTW, can you please help me to book my flight ticket? 
 agent: Sure, I am here to help you out. May I know your travelling dates please? 
 customer: Sure, I will depart on Jan 5th and I want to return back on Jan 7th. 
 agent: How much you can afford for airfare? 
 customer: I can only afford 500. 
 agent: Wait a moment please. 
 customer: Sure. 
 agent: May I know your name pleas to proceed further? 
 customer: Sure, my name is Catherine Mitchell. 
 agent: Catherine Mitchell, there are no flights available in you route. 
 customer: Not an issue, I will find an other way to reach my destination. Anyway, thank you. 
 agent: Thank you for choosing us.

Ex Output:
no_flight


Ex Input:
customer: Hi. 
 agent: Hello. How can I assist you? 
 customer: Due to bad weather conditions, I cannot attend my meeting. Can you help me to change my existing reservation? 
 agent: Sure, may I know your name? 
 customer: Sure, my name is Frank Perez. 
 agent: Please give me a moment to check your ticket status. 
 customer: Ok. 
 agent: Sorry Frank, no reservation is available by your name. 
 customer: That's ok, thank you. 
 agent: Thank you for contacting us.

Ex Output:
no_reservation