https://111qqz.com/en/tags/%E9%94%99%E6%8E%92%E5%85%AC%E5%BC%8F/Recent content in 错排公式 on 111qqz's blogHugo -- gohugo.ioen© 2015-2026 111qqzWed, 27 Jul 2016 12:06:46 +0000https://111qqz.com/en/post/acm-icpc/2016/2016-07-27-hdu-2049/Wed, 27 Jul 2016 12:06:46 +0000https://111qqz.com/en/post/acm-icpc/2016/2016-07-27-hdu-2049/<p><a href="http://acm.hdu.edu.cn/showproblem.php?pid=2049" target="_blank" rel="noreferrer">hdu 2049 题目链接</a> 题意：n个妹子和n个汉子对应。。然后让每个汉子取选一个妹子，不能重复，问恰好有m个汉子选错妹子的可能的方案数。</p>https://111qqz.com/en/post/acm-icpc/2016/2016-07-27-hdu-2048/Wed, 27 Jul 2016 08:18:13 +0000https://111qqz.com/en/post/acm-icpc/2016/2016-07-27-hdu-2048/<p><a href="http://acm.hdu.edu.cn/showproblem.php?pid=2048" target="_blank" rel="noreferrer">hdu2048 题目链接</a></p> <p>题意:n个人不放回的从一个有n个每个人对应id的卡片的盒子取一张卡片，取的正好和自己的对应就算中奖。求所有人都没有中奖的概率。</p>