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 can I help you today? 
 customer: I am Jennifer Lopez. As my hobby is gardening, I want to collect different varieties of plants by attending flower festival.Can you book a flight ticket to New York, EWR? 
 agent: Sure, please share your planned trip dates? 
 customer: Journey dates are 06/14 to 06/16. 
 agent: Ok, let me know your boarding point? 
 customer: Source code is Phoenix, PHX. 
 agent: Any other requirements to be met? 
 customer: I need a stopover in between my journey. 
 agent: Ok, please wait for a while. 
 customer: Sure. 
 agent: Thanks for waiting, no flights found with your requested details. 
 customer: No problem. Thank you. 
 agent: Ok, thank you for opting us.
Output:
no_flight