You are shown a conversation between a user and system. Identify who has spoken the indicated sentence based on the conversation.

Example Input: Sentence1: I'm departing from Norwich and want to arrive by 13:00. Sentence2: Yes, I will need a train to cambridge on thursday. Sentence3: You are booked for 7 people, 5 nights starting thursday. Your reference number is ZFREK5SQ . May I help you with anything else today? Sentence4: the Kirkwood House is in the north and it sports a four star rating. It has internet and parking and the price range is moderate. Would you like to book? Sentence5: You're welcome. Have a great time! Sentence6: The travel time of that train is 79 minutes. Sentence7: thanks for your help you have been great! Sentence8: That sounds perfect. Can you reserve it for seven people? Sentence9: Where will you be departing from? Sentence10: I'm looking for a particular hotel called the kirkwood house. Where is it, and what other information do you have about it? Sentence11: TR3078 departs at 11:16 and arrives by 12:35. Would you like a ticket? Sentence12: not right now, what's the travel time on that ride? Sentence13: Sure, I can book it for you. What day did you want to arrive and for how many days? Sentence14: 5 nights starting Thursday. Question: Who has spoken the sentence 4? (A) User (B) System
Example Output: Answer: (A) User

Example Input: Sentence1: Does it have four stars? Sentence2: Not yet, but can you tell me what time the train arrives in Ely please? Sentence3: acorn guest house is located in 154 chesterton road should i book it for you? Sentence4: I would like to leave on Tuesday after 18:00. Sentence5: It arrives by 20:07! Anything else love? Sentence6: TR5511 leaves Cambridge for Ely at 20.07. Do you need tickets? Sentence7: I've booked your stay at the Acorn Guest House, and your reference number is IT07BRTC . Sentence8: The trip will last 17 minutes. Is there anything else you would like to know? Sentence9: Do you know what day or time you want to leave? Sentence10: Thank you for using Cambridge TownInfo centre. Please consider us for your future travel needs. Sentence11: I need some lodging accommodations. It needs to have free parking and Internet please! Sentence12: I would like someone to book me a place with free parking and internet. Sentence13: That should do it. Thanks so much for your help! Sentence14: I found 29 hotels matching your request. What price range and area of town would you prefer? Sentence15: Thanks a lot. Can you also help me find a train going to Ely? Sentence16: Yes. Please book it for 2 people for 4 nights starting Friday. Sentence17: Yes it does. Shall I book? Sentence18: What is the total travel time on that time? Question: Who has spoken the sentence 15? (A) User (B) System
Example Output: Answer: (B) System

Example Input: Sentence1: That is all for now. Thank you so much. Sentence2: Yes, I would consider a star rating of 4. Can you pick one for me please? Sentence3: You are so welcome! You take care now, bye! Sentence4: I have booked it and here is the information-Booking was successful, the total fee is 105.6 GBP payable at the station . Reference number is : SLAC2W0W . Sentence5: There are several trains departing from Cambridge on Saturday. Where are you traveling and what time would you like to leave? Sentence6: Okay, I booked it and your reference number is CEVX0OU3 . Anything else? Sentence7: huntingdon marriott hotel is a 4 star hotel Sentence8: Yes please! I want to book it for 8 people for 4 nights starting tuesday Sentence9: There are multiple trains leaving that day after 12. First one departs at 12:06. Sentence10: Yes, the Huntingdon Marriott Hotel has free WiFi. Would you like me to book it for you? Sentence11: I'm sorry, I am not able to find a 5 star hotel with free internet. Would you consider a 4 star hotel? There are 3 of those. Sentence12: Oh I almost forgot can you help me find a 5 star hotel with free internet? Sentence13: Thank you that is all I need Sentence14: Ok and does that have free wifi? Sentence15: I'm going to Peterborough and want to leave after 12:00. Sentence16: Book the first one for 8 people please. Sentence17: Can you help me find a train departing out of cambridge this saturday? Sentence18: Thank you for contacting us. Have a nice day. Question: Who has spoken the sentence 2? (A) User (B) System
Example Output:
Answer: (A) User