Given the task definition, example input & output, solve the new input case.
You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.
Example: Sentence1:i need a place to dine in the center thats expensive Sentence2: I have several options for you; do you prefer African, Asian, or British food? Sentence3: Any sort of food would be fine, as long as it is a bit expensive. Could I get the phone number for your recommendation?Question: Who has spoken the sentence 2? (A) User (B) System
Output: Answer: (A) User
The sentence 1 is said by a user because the intent of it says that the information has to be gathered from the system

New input case for you: Sentence1: I want to arrive by 15:45 Sentence2: Kings Lynn. I need 5 tickets and my reference number Sentence3: My arrival destination is Cambridge. Sentence4: Any more details you would like to provide? The TR7423 leaves Cambridge on Sunday at 5, heads to London Kings Corss and arrives at 5:51. Sentence5: Train TR2257 has been booked for 5 seats. Your reference number is E720WBAI . Can I assist you with anything else today? Sentence6: Okay when would you like to leave by? Sentence7: There are many trains running on Monday, what is your arrival destination? Sentence8: I would like to travel on Sunday please. Sentence9: Yes that would be great also I need the reference number after you book it. Sentence10: TR2257 will arrive at 14:58. Should I go ahead and book 5 tickets for this train? Sentence11: I'm sorry, my booking system seems to be down. Can you try again later? Sentence12: That won't be a problem. Can you please provide me with some addition details? For example, what day and time you'd like to travel? Sentence13: I could use some help finding a train for my stay with you. Sentence14: Thank you for using our service today! Sentence15: Oops. Sorry. My travel day is Monday not Sunday. What do you have for that day. Sentence16: Yea that is okay THank you Sentence17: no thanks that's all Sentence18: What is your departure site? Question: Who has spoken the sentence 1? (A) User (B) System
Output:
Answer: (B) System