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, How can I help you? 
 customer: Can you help me to book a flight from LAS to AUS? 
 agent: Sure, May I know the travelling dates? 
 customer: My travelling dates are 11/29 and 12/01. 
 agent: Do you have any connection limit? 
 customer: I need a connecting flight. 
 agent: Do you have any preference in airline? 
 customer: I prefer normal cost airline. 
 agent: May I know your name? 
 customer: My name is Pamela Wilson. 
 agent: Please wait a minute. 
 customer: Ok. 
 agent: Sorry, No flights found with your chosen dates. 
 customer: No issues, thank you for your time. 
 agent: Thank you for opting us.

Ex Output:
no_flight


Ex Input:
customer: Hello. 
 agent: Hello. 
 customer: I am Christopher Edwards. 
 agent: How may I guide you today? 
 customer: Can you help me to find a flight from MSP to IAD? 
 agent: Sure, I will help you with that. Can you please share your preferable journey dates? 
 customer: My travelling dates are July, 15 and July, 17. 
 agent: Do you have any specifications? I am sorry to say that there is no reservation found under your details. 
 customer: That's fine, thanks for your information. 
 agent: Thank you for reaching us.

Ex Output:
no_flight


Ex Input:
customer: Hello. 
 agent: Hello, how may I be at your service today? 
 customer: Can you help me to book a flight ticket from DEN to MSP? 
 agent: Sure, I will help you in booking the ticket. May I know your travelling dates please? 
 customer: My travel dates are Mar, 16 and Mar, 18. 
 agent: Do you have any other specifications? 
 customer: I need connecting flight. 
 agent: Please help me with your name for booking. 
 customer: Stephanie Phillips here. 
 agent: Sorry for this inconvenience, I could not find any flight with your requirements. 
 customer: Not a problem, thank you for the information. 
 agent: Thank you for reaching us.

Ex Output:
no_flight