You will be given a definition of a task first, then some input of the task.
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

customer: Hello. 
 agent: Hello, how can I assist you? 
 customer: I would like to visit Las Vegas to meet my uncle, please help me in booking a ticket from SFO to LAS. 
 agent: Sure, I am glad to help you with that. Can you please provide your preferable dates of travelling? 
 customer: My planned travel dates are on Dec 1 and Dec 3. 
 agent: May I know your name? 
 customer: My name is Brenda Turner. 
 agent: Do you need any connections between your trip? 
 customer: I need a flight with single connection. 
 agent: Do you need any other requirements? 
 customer: I would like to depart in the evening. 
 agent: As per your requirements there is a Frontier airlines, flight number:1007 is going on your way with single connection and price:100. Is that Ok for you? 
 customer: Ok, please proceed for booking. 
 agent: Your ticket has been booked successfully. 
 customer: Thank you for your assistance. 
 agent: Thank you for opting us.
Output:
book