Definition: 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: Can you please help me to search a flight with 0 connection limit? 
 agent: Can you help me by giving your planned dates? 
 customer: Sure, the planned dates are 05/31 to 06/02. 
 agent: Ok, may I know your locations? 
 customer: The airport codes are from CA-LAX to NC-CLT. 
 agent: Fine, let me know your name? 
 customer: Sure, my name is Amy Roberts. 
 agent: According to your information, there is no flight for you on your route. 
 customer: Ok, no problem. Thank you. 
 agent: Thank you for choosing us.
Output:
no_flight