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. 
 customer: I am Gregory Evans from Denver. 
 agent: I am here to assist you, please can I know your concern? 
 customer: I want to go Boston next month, can you please book a direct flight for me? 
 agent: Yes Evans, I will try my best to provide you a ticket with direct flight. May I know your travel airport codes? 
 customer: Thank you, I want to take off from DEN and book my return ticket also on BOS. 
 agent: Please can I know your travel dates? 
 customer: My travel dates are 06/24 and 06/26. 
 agent: As per your request there is no direct flight from your location, sorry for the incoveniences. 
 customer: Oh! It's ok no problem, I will go with another airline. 
 agent: Thank you for availing our service. 
 customer: You are welcome.
Output:
no_flight