Instructions: 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
Input: customer: Hi. 
 agent: Hello. 
 customer: Shirley Moore here. 
 agent: What service you are looking for? 
 customer: Reserve a flight ticket for me that is from DTW to HOU. 
 agent: Sure. What are your departure date and return date? 
 customer: My travelling dates for journey are 06/16 to 06/18. 
 agent: Ok, do you have any other requirements? 
 customer: look for single connecting flight. 
 agent: Ok. I will check the fight,  please wait a minute. 
 customer: Sure. 
 agent: There is a flight with single connection, the airlines is UA and the price is 200. Can I confirm your ticket? 
 customer: Sure, you can confirm the flight ticket. 
 agent: Ok, your ticket is confirmed with the service number 1004. 
 customer: Thank you. 
 agent: It's my pleasure. Thank you for choosing us.
Output:
book