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. I am Christine Scott. 
 agent: Hello, how can I aid you today? 
 customer: I would like to book a ticket from ORD to DCA, can you please help me out? 
 agent: Sure, when are you planning to start and return on? 
 customer: I am travelling on these dates AUG 11th and 13th. 
 agent: Do you need a connecting flight or a direct flight? 
 customer: I need a connecting flight. 
 agent: There are no flights found with the given details. 
 customer: Ok no problem, thank you for your services. 
 agent: Thank you, please visit again.
Output:
no_flight