You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. May I know your name?

USER: Sure, my name is Ronald Lopez.

ASSISTANT: What can I do for you today?

USER: I want to meet my childhood friends on 05/16 to 05/18.Can you please help me out?

ASSISTANT: Sure, may I know the airport codes?

USER: The corresponding airport codes are from DC-IAD to CA-OAK.

ASSISTANT: Sure, give me a minute.

USER: Ok.

ASSISTANT: I found a ticket for you.The price is 100 and flight number is 1000. Is it ok for you?

USER: That's fine, proceed with my booking.

ASSISTANT: Thank you for the information. Your ticket is confirmed successfully.

USER: Thank you for your service.

ASSISTANT: Welcome.