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. 
 agent: Hello, how best can I guide you for the day? 
 customer: Can you help me to book a flight from my work location Phoenix, PHX to Houston, HOU? 
 agent: Sure, do you prefer a connecting flight? 
 customer: Ok, please book a connecting flight. 
 agent: When do you want to start and return on? 
 customer: Ok, please book a flight for the dates June 22nd and June 24th. 
 agent: Do you prefer any other specifications? 
 customer: No. 
 agent: Can I know your good name? Thank you for your details, we found a connecting flight 1025 in class economy which is in Hawaiian airline. 
 customer: Ok, please book a ticket on the name Jeffrey Lopez. 
 agent: Your ticket has been confirmed. 
 customer: That is great, thank you for assisting me.

Ex Output:
book


Ex Input:
customer: Hello. 
 agent: Hello, how may I assist you today? 
 customer: Edward Young here. I would like to change my recent reservation, can you help me? 
 agent: Ok, let me check with your existing reservation for a moment. 
 customer: Sure. 
 agent: Thank you for waiting. 
 customer: It's ok. 
 agent: I'm so sorry to inform you, there is no reservation found by your name in our data base. 
 customer: That's fine, anyway thanks for your help and valuable information. 
 agent: Thank you for approaching our agency.

Ex Output:
no_reservation


Ex Input:
customer: Hello. I am Michael Lopez. 
 agent: Hello, how can I help you today? 
 customer: I need to book a ticket to meet my parents on 05/15. Could you please help me in booking a return ticket on 05/17? 
 agent: Sure, please share me your source and destination. 
 customer: My source and destination code is DTW and LAS. 
 agent: May I know your connection limit? 
 customer: I need a stopover in between the journey. 
 agent: Please wait for a moment. I will check the availability of the flights. 
 customer: Sure. 
 agent: We are glad to say that, we found an airline: UA, flight number: 1002 with a single connection and price is 100. 
 customer: You can proceed with booking. 
 agent: Your flight ticket has been reserved. 
 customer: Thank you for your quick response. 
 agent: Thank you for opting us.

Ex Output:
book