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

[Q]: Sentence1: Booking was successful for Tuesday. Your Reference number is : 0J3V1091 . Sentence2: I'm sorry that doesn't seem to be available would you like me to try a different day or guesthouse? Sentence3: I'm sorry, there does not seem to be a historical site or hiking area in Cambridge. Is there anything else I can help with? Sentence4: Sure, I can help you with that. What section of town were you looking for? Sentence5: Doesn't really matter if they offer either of those or not. I just want it to be a 0 star hotel. Sentence6: Then the city centre north b and b is what you want, shall I book you? Sentence7: i don't really care about the area. Sentence8: I want to see local sights, can you help? Sentence9: I like hiking and seeing historical sites. Sentence10: Okay. Are you interested in hotels that offer internet and/or parking? Sentence11: Yes, I would like to find a hotel in the cheap price range? Sentence12: Yes, a guesthouse is fine. I was looking for zero stars and in the cheap price range. Sentence13: Great, thanks. I don't need anymore help. Goodbye! Sentence14: Yes, please book it for me. Sentence15: I'm sorry, I seem to be having an error in my system. You want a booking at the citycentre north B&B for 6 people, 5 nights, on Monday? Sentence16: I'm also looking for somewhere to go. Perhaps the college. Can you tell me the postcode for the college? Sentence17: City Cenrtree North and B is a cheap hotel,would you like me to book it for you ? Sentence18: Let book the same but on Tuesday instead. Sentence19: I'm happy I could help today. Goodbye! Sentence20: There are 18 colleges in town. I recommend christ's college in the centre. The postcode is cb23bu. Sentence21: Yes, there is a wide variety, do you have an activity type that your are interested in? Sentence22: Yes please, 6 people for 5 nights and we would be arriving Monday. Question: Who has spoken the sentence 21? (A) User (B) System
[A]: Answer: (B) System


[Q]: Sentence1: No thank you. Im finished. Sentence2: Allenbell is my favorite. It has four stars. The phone number is 01223210353. Shall I book that for you? Sentence3: Is there anything else I can help you with? Sentence4: I found 10 places, do you have a hotel style preference of gueshouse or hotel, or an area you prefer? Sentence5: You're welcome. How many people are in your party, and when will you arrive? Also, how long would you like to stay? Sentence6: I'm looking for a cheap place to stay that does not need free parking. Sentence7: It sounds fine. Do any of them include free wifi? Sentence8: There are three cheap guesthouses in the east area, however, they all have parking. Will this be okay, or would you like to look at a different area or price? Sentence9: Okay. Have a good day. Sentence10: That'd be great. Thank you. Sentence11: All of them include free wifi. Sentence12: What's the phone number and star rating of your favorite one? Sentence13: I will book on my own, thanks. Sentence14: I don't have a preference for the type but I would like a place in the east. Question: Who has spoken the sentence 7? (A) User (B) System
[A]: Answer: (B) System


[Q]: Sentence1: Thanks, that is all I need on the hotel but can I book a train from cambridge to stevenage, I need to arrive by 20:45 and leave at 05:00. Sentence2: I just need the departure time and price please Sentence3: It is called home from home. I was wondering what type of hotel it is and the star of the hotel. Sentence4: I have trains available would you like me to book that for you? Sentence5: I would like to leave on Thursday. Sentence6: I'll be more than happy to help you book the train. What day do you want to leave? Sentence7: Yes, hopefully you can help with some information on a particular hotel? Sentence8: Home from Home is a 4 star, guesthouse type hotel. Sentence9: leave at 5:21 and arrive by 6:10 for 12.80 pounds Sentence10: What hotel are you interested in? Question: Who has spoken the sentence 2? (A) User (B) System
[A]:
Answer: (A) User