Teacher: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
Teacher: Now, understand the problem? Solve this instance: customer: Hi, I am Ronald Young. 
 agent: Hello, how can I guide you for today? 
 customer: Can you please reserve me a direct flight from Denver, CO - DEN to Houston, TX - HOU? 
 agent: Can you please share on what dates you are willing to travel? 
 customer: My trip dates are 04/18 - 04/20. 
 agent: Please give me a minute, I will check the availability of flights on this route. 
 customer: Sure. 
 agent: There is a flight with ticket fare 200 in Hawaiian airlines with a stopover. Is it ok for you? 
 customer: Please reserve. 
 agent: Your booking is confirmed with flight number 1000. 
 customer: Thank you. 
 agent: Thank you for contacting us, have a nice day.
Student:
book