Given the task definition and input, reply with output. 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 may I assist you today? 
 customer: I am planning to attend a Hockey competition in DCA from LAS. Can you find a flight ticket for me? 
 agent: Sure, may I know your planned travel dates? 
 customer: Ok, my planned trip dates are on Sept 05 and return on Sept 07. 
 agent: Do you have any specifications on your journey? 
 customer: Ok, I need a single connecting flight. 
 agent: May I know your name for the booking process? 
 customer: Ok, my name is Susan Roberts. 
 agent: Spirit Airlines providing a flight with the price 100 with single connection. Can I proceed for the booking? 
 customer: Please go ahead with the ticket booking. 
 agent: Your ticket reservation done with the flight number 1000. 
 customer: Thank you for your help. 
 agent: Welcome, thank you for reaching us.
book