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. 
 customer: Frank Hall here. 
 agent: How may I guide you today? 
 customer: I want to travel from LGA to EWR for attending a Seminar. Can you please help me for booking the flight ticket? 
 agent: Sure, I will help you with that. Can you please share your preferable journey dates? 
 customer: My travelling dates are from 08/07 to 08/09. 
 agent: Please wait for a minute. 
 customer: Ok, I will wait. 
 agent: I am sorry to say that there is no flight found. 
 customer: Anyway, thanks for the information. 
 agent: Thank you for reaching us.
Output:
no_flight