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 today? 
 customer: I have a meeting with foreign delegates at San Francisco. Can you help me in booking a ticket? 
 agent: Sure, please share your airport codes. 
 customer: The airport codes are EWR and SFO respectively. 
 agent: On which dates do you want to travel? 
 customer: I am planning my journey on dates 02/26 and 02/28. 
 agent: Please may I know your name? 
 customer: My name is Samuel Moore. 
 agent: Flight 1022 of AA airline  available for you on your route with 1 connection. 
 customer: Please book the ticket. 
 agent: Your ticket is confirmed successfully. 
 customer: Thank you for your assistance. 
 agent: Thank you for choosing us, have a good day.
Output:
book