https://111qqz.com/en/tags/%E7%AC%AC%E4%BA%8C%E7%B1%BB%E6%96%AF%E7%89%B9%E6%9E%97%E6%95%B0/Recent content in 第二类斯特林数 on 111qqz's blogHugo -- gohugo.ioen© 2015-2026 111qqzFri, 14 Aug 2015 22:20:00 +0000https://111qqz.com/en/post/acm-icpc/2015/2015-08-14-codeforces569d/Fri, 14 Aug 2015 22:20:00 +0000https://111qqz.com/en/post/acm-icpc/2015/2015-08-14-codeforces569d/<p>D. Symmetric and Transitive</p> <p>time limit per test</p> <p>1.5 seconds</p> <p>memory limit per test</p> <p>256 megabytes</p> <p>input</p> <p>standard input</p> <p>output</p> <p>standard output</p> <p>Little Johnny has recently learned about set theory. Now he is studying binary relations. You&rsquo;ve probably heard the term &ldquo;equivalence relation&rdquo;. These relations are very important in many areas of mathematics. For example, the equality of the two numbers is an equivalence relation.</p>