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链接: https://codeforces.com/contest/1220/problem/E 题意: Alex decided to go on a touristic trip over the country. For simplicity let's assume that the co 阅读全文
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链接: https://codeforces.com/contest/1220/problem/D 题意: Boy Dima gave Julian a birthday present set B consisting of positive integers. However, he didn' 阅读全文
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链接: https://codeforces.com/contest/1220/problem/C 题意: Mike and Ann are sitting in the classroom. The lesson is boring, so they decided to play an inte 阅读全文
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链接: https://codeforces.com/contest/1220/problem/B 题意: Sasha grew up and went to first grade. To celebrate this event her mother bought her a multiplic 阅读全文
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链接: https://codeforces.com/contest/1220/problem/A 题意: When Serezha was three years old, he was given a set of cards with letters for his birthday. The 阅读全文