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: Please book a ticket from Phoenix, AZ-PHX to Washington DC-IAD. 
 agent: Sure, please share your travelling dates. 
 customer: Depart date is 01/12 and 01/14 is return. 
 agent: We found a flight with single connection and price is 100 of 1016 flight. Shall I proceed for booking? 
 customer: Please book a flight. 
 agent: Your ticket has been confirmed with UA airlines. 
 customer: Thanks. 
 agent: May I know your name? 
 customer: My name is Melissa Walker. 
 agent: Thank you. 
 customer: Thanks.
Output:
book