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 may I oblige you today? 
 customer: I have to go Oakland to meet my friend over there so please help me with flight ticket booking from Houston. 
 agent: Sure, please share your planned trip dates? 
 customer: Thank you. I have planned my travel dates as Jan 08 and Jan 10. 
 agent: Let me know your connection limit? 
 customer: I would prefer single connecting flight so please  check with that. 
 agent: May I know your Origin code? 
 customer: Sure, HOU is the airport code of my starting point. 
 agent: Do you have any airline preference? 
 customer: Yes, I am looking for normal cost airlines. 
 agent: Ok, any other requirements to be met? 
 customer: My destination airport code is OAK. 
 agent: May I know your name please? 
 customer: Sure, myself Amy Martin. 
 agent: Sorry, there are no flights found with your given details. 
 customer: Oh! It is sad to hear. Anyway, thank you for your time. 
 agent: Thank you for reaching us.
Output:
no_flight