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

Ex Input:
customer: Hello. I am Joshua Collins. 
 agent: Hello, how can I help you today? 
 customer: Can you please book a flight ticket from DTW to JFK? 
 agent: Sure, I will help you with it. Please share me your planned travel dates to proceed further. 
 customer: Thank you. Sure, I need to travel on dates of Sept 21 and Sept 23. 
 agent: Do you prefer any specific time for you depart and return? 
 customer: Yes, I would like to depart in morning time only. 
 agent: Please let me know if you have any other preferences. 
 customer: I need connection 1 so please check with that. 
 agent: Thank you for providing all the essential details, please wait for a while. 
 customer: Sure, I am happy to wait for your response. 
 agent: We are sorry to inform you that we don't have any flight available in the morning time on given dates by you. 
 customer: Oh! It is sad to hear. Anyway, thank you for your time. 
 agent: Thank you, looking forward to serve you better next time. 
 customer: Most welcome.

Ex Output:
no_flight


Ex Input:
customer: Hello. 
 agent: Hello. How can I aid you? 
 customer: Can you aid me to book a ticket from MSP to AUS? 
 agent: Sure, can I have your travelling dates please? 
 customer: My trip dates are June 9 and June 11 respectively. 
 agent: Please provide your specifications. 
 customer: Make sure that connection limit is single. 
 agent: May I know your good name please? 
 customer: David Carter here. 
 agent: Unfortunately there is no flight found with your given details. 
 customer: Oh! ok. 
 agent: Thank you for reaching us. 
 customer: Thank you.

Ex Output:
no_flight


Ex Input:
customer: Hello. 
 agent: Hello, how may I aid you? 
 customer: Please book a flight ticket from DEN to IAH? 
 agent: May I know your travelling dates? 
 customer: My journey dates are Nov 04 and Nov 06. 
 agent: Is there any connection limit? 
 customer: I need a connecting flight. 
 agent: May I know your good name? 
 customer: I am Carol Harris. 
 agent: Any more requirements? 
 customer: No. 
 agent: Spirit Airlines providing connecting flight in the economy class with fare 100, shall I proceed for booking? 
 customer: Go ahead. 
 agent: Your ticket has been confirmed with flight number 1018. 
 customer: Thank you for your information. 
 agent: Thank you for choosing us.

Ex Output:
book