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
Q: customer: Hi. I am Gary Campbell. 
 agent: Hello, how may I serve you at this moment? 
 customer: I need to cancel my reservation as my exams got cancelled, can you please help me out in cancellation? 
 agent: Sure, I will help you. Please wait for a moment. 
 customer: Ok. 
 agent: I have found your reservation, shall I cancel it? 
 customer: Yes, you can. 
 agent: Your booking is cancelled successfully. 
 customer: Thank you. 
 agent: You are welcome, have a nice day.
A:
cancel