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: Hello. 
 agent: Hello. How may I assist you? 
 customer: I am looking for a flight from OAK to JFK, can you help me in booking? 
 agent: Sure, can you please share your planned trip dates? 
 customer: Sure, my planned travel dates are Jan 09 and Jan 11. 
 agent: May I know your name please to proceed further? 
 customer: Myself Melissa Martinez. 
 agent: Do you need a connecting flight or a direct flight? 
 customer: I prefer for a connecting flight. 
 agent: Do you have any other specifications? 
 customer: No. 
 agent: Melissa Martinez, no flights has been found on your planned journey dates. 
 customer: That's ok, no problem. Thank you for the information. 
 agent: Thank you for choosing us.
Output:
no_flight