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

Example input: customer: Hi. 
 agent: Hello. How can I help you? 
 customer: I would like to change my existing reservation as my plan to go for a holiday trip got postponed. Can you please help me with this? 
 agent: Sure, may I know your name please? 
 customer: My name is Anthony Phillips. 
 agent: Please wait a moment. 
 customer: Sure. 
 agent: Unfortunately there is no reservation found with your given name. 
 customer: Not a problem, thank you for checking. 
 agent: Thank you for choosing us.
Example output: no_reservation
Example explanation: Here the customer has not asked for any booking, he just wanted to update his already booked flight, so the status would be no_reservation
Q: customer: Hello. 
 agent: Hello. 
 customer: Sandra Phillips here. 
 agent: How may I guide you today? 
 customer: I want to book a flight on the route from HOU to LAS, can you help me? 
 agent: Sure, I am glad to help you with that. Can you please provide your planned dates of travelling? 
 customer: My travelling dates will be from 05/22 to 05/24. 
 agent: Please wait a moment to check the flights on your route. 
 customer: Ok, take your time. 
 agent: Based on your travel details, I have found a flight with a single connection with a fare of 100 from Spirit airlines. If you are ok with this, please inform me to book the flight. 
 customer: You can proceed with booking my ticket. 
 agent: Ok, your ticket has been confirmed in flight number 1026. 
 customer: Thank you for helping me with booking. 
 agent: Thank you for reaching us, have a great journey. 
 customer: Most welcome.
A:
book