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. 
 agent: Hello. What help that I can assist you? 
 customer: I want to change an existing  reservation due to sudden change in my trip. Can you help me? 
 agent: Sure, I can help you and can you please mention your name for checking purpose? 
 customer: Paul Collins. 
 agent: Please wait for a moment. 
 customer: Ok. 
 agent: Thank you for waiting, I have checked in reservation list to change your ticket but could not find any reservation with your name. 
 customer: No issue. Thank you. 
 agent: Thank you for reaching us, have a nice day.

Ex Output:
no_reservation


Ex Input:
customer: Hi. 
 agent: Hello. How may I help you? 
 customer: Can you pleas check for the flights from Dec 21 to Dec 23. 
 agent: Sure, what are your trip source and destination? 
 customer: My airport codes are from ORD to DFW. 
 agent: Do you need any connections? 
 customer: Please check for 1 connecting flight. 
 agent: Are there any other preferences? 
 customer: I will be returning in afternoon with economy class. 
 agent: May I know your name? 
 customer: My name is Sandra King. 
 agent: Sorry, there is no flight found with your details. 
 customer: Oh! That's fine. Thank you for checking. 
 agent: Thank you for reaching us. 
 customer: Most welcome.

Ex Output:
no_flight


Ex Input:
customer: Hi. I am Jessica Evens. 
 agent: Hello,. How may I serve you? 
 customer: I want to book a flight ticket on  01/04 to 01/06 for which I have a exam at IAH. 
 agent: Sure, may I know your origin point? 
 customer: My source code is ATL. And I want with 1 connection. 
 agent: Sorry to inform that there is no flight found with your specification. 
 customer: Ok. Thank you for  information and your service. 
 agent: Thank you for reaching us.

Ex Output:
no_flight