{"id":640,"date":"2013-01-22T05:18:58","date_gmt":"2013-01-21T21:18:58","guid":{"rendered":"http:\/\/www.shuizilong.com\/house\/?p=640"},"modified":"2013-01-23T05:26:00","modified_gmt":"2013-01-22T21:26:00","slug":"codechef-january-challenge-2013","status":"publish","type":"post","link":"https:\/\/www.shuizilong.com\/house\/archives\/codechef-january-challenge-2013\/","title":{"rendered":"CodeChef January Challenge 2013"},"content":{"rendered":"<p><a href=\"http:\/\/www.codechef.com\/JAN13\/\">http:\/\/www.codechef.com\/JAN13\/<\/a><\/p>\n<p><!--more--><\/p>\n<h2 style=\"color: #7B5E47;\">Level 2. Dividing Products<\/h2>\n<h3>Brief description: <\/h3>\n<p>\u5b9a\u4e49 &#8220;\u4ea4\u9519\u4e58\u9664&#8221; DIVPRO(x) \u4e3a\u3002\u3002 x \u7684\u5341\u8fdb\u5236\u5c55\u5f00\u540e\u3002\u3002\u4ea4\u9519\u76f8\u4e58\u76f8\u9664\u3002\u3002<br \/>\n\u3002\u3002\u4f8b\u5982 x = 1234 \u90a3\u4e48 DIVPRO(x) = 1 \/ 2 * 3 \/ 4 = 3 \/ 8\u3002\u3002\uff08\u6ce8\u610f\u8fd9\u4e2a\u7ed3\u679c\u4e0d\u4e00\u5b9a\u662f\u6574\u6570\u3002\u3002\u3002\u5982\u679c\u4e2d\u95f4\u53d1\u751f\u9664 0 \u3002\u3002\u5219\u8be5\u51fd\u6570\u7684\u7ed3\u679c\u4e3a\u672a\u5b9a\u4e49\uff0c\u3002\u3002<br \/>\n\u3002\u3002\u3002\u8be2\u95ee\u6709\u591a\u5c11 L \u4f4d\u7684\u6570\u3002\u3002\u5176\u4ea4\u9519\u4e58\u9664\u7684\u7ed3\u679c\u662f V \u3002\u3002\u3002<\/p>\n<h3>Analysis: <\/h3>\n<p>\u3002\u3002\u5982\u679c\u9884\u5904\u7406\u5904\u7406\u6d88\u8017\u65f6\u95f4\u592a\u591a\u3002\u3002\u6216\u8005\u5185\u5b58\u6d88\u8017\u592a\u5927\u3002\u6839\u672c\u8fc7\u4e0d\u53bb\u3002\u3002\u3002<br \/>\n\u3002\u5982\u679c\u9884\u5904\u7406\u592a\u5c11\u3002\u56e0\u4e3a\u6570\u636e\u7ec4\u6570\u592a\u591a\u3002\u3002\u540e\u9762\u4f1a TLE \u3002\u3002\u3002<\/p>\n<p>\u3002\u6240\u4ee5\u8fd9\u4e2a\u9898\u3002\u3002\u5c31\u662f\u5982\u4f55\u5728\u9884\u5904\u7406\u548c\u4e8b\u5b9e\u8ba1\u7b97\u4e2d\u95f4\u3002\u6700\u5927\u7a0b\u5ea6\u7684\u5229\u7528\u9898\u8bbe\u4e2d\u7684\u9650\u5236\u6761\u4ef6\u3002\u3002\u3002\u5bfb\u627e\u5e73\u8861\u3002\u3002\u3002\u3002<br \/>\n\u3002\u3002\u4ee5\u4e0b\u662f\u6700\u91cd\u8981\u7684\u51e0\u70b9\u89c2\u5bdf\u3002\u3002<\/p>\n<ul>\n<li>\u8be2\u95ee\u7684\u7ed3\u679c\u90fd\u662f\u6574\u6570\u3002<\/li>\n<li>0 \u7684\u60c5\u51b5\u975e\u5e38\u7279\u6b8a\u3002\u3002\u9700\u8981\u7279\u5224\u3002<\/li>\n<li>\u4e58\u3001\u9664\u9700\u8981\u5206\u5f00\u5904\u7406\u3002\u3002\u4e14\u90fd\u770b\u505a \u201c\u4e58\u201d \u7684\u60c5\u51b5\u3002\uff08\u628a\u4e58\u7684\u7ed3\u679c\u8bb0\u4f5c a\uff0c\u9664\u7684\u7ed3\u679c\u8bb0\u4f5c b\u3002\u3002\u5219\u5c31\u662f\u627e\u5230\u8ba1\u6570\u6240\u6709\u6ee1\u8db3 a \/ b = V \u7684 a \u548c b \u3002\u3002\u3002<\/li>\n<li>\u53ea\u9700\u8981\u8003\u5bdf 2, 3, 5, 7 \u56db\u4e2a\u56e0\u5b50\u3002\u3002<\/li>\n<li>\u30025, 7 \u56e0\u5b50\u82e5\u51fa\u73b0\u3002\u3002\u90fd\u5fc5\u7136\u4f1a\u5b8c\u6574\u7684\u5360\u636e\u4e00\u4e2a\u4f4d\u5b50\u3002\u3002<\/li>\n<\/ul>\n<p>\u3002\u3002\u7efc\u5408\u8003\u8651\u4ee5\u4e0a\u51e0\u70b9\u53ef\u5f97\u5230\u7b97\u6cd5\u3002\u3002<\/p>\n<ul>\n<li>\u3002\u679a\u4e3e a \u6216 b \u5176\u4e2d\u4e00\u4e2a\u7684 5\u30017 \u56e0\u5b50\u3002\u3002\u5219\u53e6\u4e00\u4e2a\u7684 5\u30017 \u56e0\u5b50\u53ef\u4ee5\u8ba1\u7b97\u51fa\u3002\u3002<\/li>\n<li>\u3002\u4e24\u6b21 DP \u9884\u5904\u7406\u3002\u3002\u7b2c\u4e00\u6b21\u53ea\u8003\u5bdf\u4e58\u79ef\u7684\u60c5\u51b5\u3002\u3002_dp[i][p2][p3] \u8868\u793a\u5f53\u524d\u4f7f\u7528\u4e86 i \u4e2a\u4f4d\u7f6e\u3002\u3002\u4ea7\u751f\u4e86 p2 \u4e2a 2 \u56e0\u5b50\u3002\u548c p3 \u4e2a 3 \u56e0\u5b50\u3002\u7684\u65b9\u6848\u603b\u6570\u3002\u3002\u3002<\/li>\n<li>\u3002\u7b2c\u4e8c\u6b21 dp[i][ii][p2][p3]\u3002\u8868\u793a\u3002\u4e58\u6570\u4f4d\u7f6e\u7528\u4e86 i \u4e2a\u4f4d\u7f6e\u3002\u3002\u9664\u6570\u4f4d\u7f6e\u7528\u4e86 ii \u4e2a\u4f4d\u7f6e\u3002\u3002\u4ea7\u751f\u4e86 p2 \u4e2a 2 \u56e0\u5b50\u3002\u3002p3 \u4e2a 3 \u56e0\u5b50\u3002\uff08\u8fd9\u6837\u5c31\u4e0d\u9700\u8981\u8003\u8651\u4e2d\u95f4 p2 \u548c p3 \u6307\u6570\u4e3a\u8d1f\u6570\u7684\u60c5\u51b5\u3002\u3002\u3002<\/li>\n<li>\u3002\u3002\u901a\u8fc7\u7ec4\u5408\u6570\u3002\u8ba1\u7b97\u6700\u540e\u7ed3\u679c\u3002\u3002\u3002<\/li>\n<\/ul>\n<p>\u3002\u3002\u3002\u5199\u7684\u65f6\u5019\u7ec6\u8282\u86ee\u591a\u7684\u3002\u3002\u3002\u56e0\u4e3a\u5185\u5b58\u6bd4\u8f83\u7d27\u3002\u3002\u6240\u6709\u4e00\u76f4\u63a7\u5236\u7740\u6570\u7ec4\u5927\u5c0f\u3002\u3002<br \/>\n\u3002\u6570\u7ec4\u5f00\u5c0f\u4e86\u3002\u5361\u4e86\u597d\u4e45\u3002\u3002\uff08\u4f46\u6211\u4e00\u76f4\u90fd\u4e00\u8fb9\u5c0f\u5fc3\u8ba1\u7b97\u6570\u7ec4\u5927\u5c0f\u4e00\u8fb9\u5f00\u7684\u3002\u3002\u5230\u73b0\u5728\u8fd8\u6ca1\u660e\u767d\u662f\u54ea\u91cc\u5f00\u5c0f\u4e86\u3001\u3001\u53ef\u89c1\u6211\u771f\u662f\u5f31\u7206\u4e86\u3002\u3002\uff08\u3002\u3001\u561b\u3002\u3002\u53cd\u6b63\u5df2\u7ecf\u8fc7\u4e86\u3002\u3002\u8ba1\u7b97\u7684\u90a3\u4e48\u4ed4\u7ec6\u5e72\u561b\u3002\u3002\u3002\u3002\uff1f\u3002\u3002<\/p>\n<h2 style=\"color: #7B5E47;\">Level 2. Hotel Balifornia<\/h2>\n<h3>Brief description: <\/h3>\n<p>\u3002\u3002\u9605\u8bfb\u7406\u89e3\u9898\u3002\u3002<\/p>\n<h3>Analysis: <\/h3>\n<p>\u3002\u3002\u3002\u5f88\u5bb9\u6613\u5c31\u6ce8\u610f\u5230\u3002\u4e2d\u95f4\u7684\u4e09\u9636\u7ebf\u6027\u9012\u63a8\u5e8f\u5217\u662f\u56fa\u5b9a\u7684\u3002\u3002\u5927\u6982\u662f\u7a81\u7834\u53e3\u3002\u3002<br \/>\n\u3002\u3002\u4e8b\u5b9e\u60c5\u51b5\u4e5f\u5c31\u662f\u5982\u6b64\u3002\u3002\u5f00\u4e00\u4e2a set&lt;pair&lt;int, int, int&gt;&gt;\u3002\u3002\u6765\u627e\u5faa\u73af\u8282\u7684\u4f4d\u7f6e\u3002\u3002<br \/>\n\u3002\u3002\u5bf9\u4e8e\u8fd9\u4e2a\u4e09\u9636\u7ebf\u6027\u9012\u63a8\u5e8f\u5217\u3002\u975e\u5e38\u6ca1\u6709\u89c4\u5f8b\u3002\u3002\u3002\u6240\u4ee5\u6253\u597d\u8868\u4ee5\u540e\u5c31\u628a set \u53bb\u6389\u3002\u3002\u5b9e\u9645\u4e0a\u53ea\u8981\u6253\u5230\u6700\u540e\u4e00\u4e2a\u53ef\u7528\u4f4d\u7f6e\u51fa\u73b0\u7684\u957f\u5ea6\u5c31\u53ef\u4ee5\u3001\u3001<br \/>\n\u3002\u3002\u3002\u3002\u3002\u89c2\u5bdf\u53d1\u73b0\u8fd9\u4e2a\u503c\u90fd\u4e0d\u5927\u3002\u3002\u5269\u4e0b\u7684\u6a21\u62df\u5373\u53ef\u3002\u3002<br \/>\n\uff08\u6ce8\u610f\u524d\u540e\u4e24\u4e2a\u65f6\u95f4\u76f8\u7b49\u7684\u60c5\u51b5\u3002\u3002<\/p>\n<h2 style=\"color: #7B5E47;\">Level 2. A New Door<\/h2>\n<h3>Brief description: <\/h3>\n<p>&#8230; \u5706\u5e76\u5468\u957f\u3002\u3002\uff08\u9650\u5236\u5728\u4e00\u4e2a\u77e9\u5f62\u533a\u57df\u5185\u3002<\/p>\n<h3>Analysis: <\/h3>\n<p>&#8230; \u8fd9\u4e2a\u5c31\u662f\u6bd4\u8d5b\u65f6\u628a\u6211\u5751\u51fa\u7fd4\u7684\u90a3\u4e2a\u9898\u3002\u3002\u3002\u3002\u5404\u79cd\u59ff\u52bf\u63d0\u4ea4\u4e86\u4e0d\u4e0b 20 \u9875\u3002\u3002\u540e\u6765\u65e0\u803b\u7684\u62c9\u4e86\u6240\u6709\u6211\u8ba4\u8bc6\u7684\u7cfb\u7edf\u5b66\u4e60\u8fc7\u8ba1\u7b97\u51e0\u4f55\u7684\u795e\u725b\u3002\u3002<br \/>\n\uff08\u4f46\u662f\u4f3c\u4e4e\u6ca1\u4e00\u4e2a AC \u7684\u3002\u3002\u3002\u6211\u90fd\u4e0d\u597d\u610f\u601d\u518d\u5751\u5176\u4ed6\u4eba\u4e86\u3002\uff08\u54ce\u5440\u6342\u8138\u3002\u3002\u3001\u3001\u3001\u3002\u3002<\/p>\n<p>\u3002\u3002\u3002\u8bfb\u4e86\u4e0b\u89e3\u9898\u62a5\u544a\u3002\u3002\u53d1\u73b0\u6240\u6709\u80fd\u60f3\u5230\u7684\u53ef\u80fd\u5751\u7684\u5730\u65b9\u3002\u3002\u6bd4\u8d5b\u65f6\u540e\u6765\u4e5f\u90fd\u60f3\u5230\u4e86\u3002\u3002\u3002\u6ca1\u529e\u6cd5\u53ea\u597d\u62ff\u6807\u7a0b\u51fa\u6765\u3002\u3002\u62ff\u6211\u7684\u4ee3\u7801\u4e00\u70b9\u70b9\u76d6\u4e0a\u53bb\u3002\u76f4\u5230\u628a\u4ed6\u641e WA \u3002\u3002\u3002<br \/>\n\u3002\u3002\u3002\u3002\u57fa\u672c\u7b97\u6cd5\u5c31\u662f\u9648\u9e3f\u7b97\u6cd5\u3002\u3002\u4e0d\u4f1a\u9648\u9e3f\u7b97\u6cd5\u7684\u3002\u3002\u5efa\u8bae\u5148\u5b66\u4e60<a href=\"https:\/\/www.shuizilong.com\/house\/archives\/spoj-8119-ciru2\/\">\u9648\u9e3f\u7b97\u6cd5(Cheng&#8217;Hong&#8217;s Algorithm)\u3002\u3002<\/a><br \/>\n\uff08\u3002\u3002\u6bd4\u8d5b\u65f6\u6709\u795e\u725b Java 1000 \u591a M \u5185\u5b58\u7206\u8fc7\u53bb\u4e86\u3002\u3002\u6211\u8fd8\u4ee5\u4e3a\u662f Laguerre V \u56fe\u3002\u3002\u975e\u5e38\u9ad8\u6b23\u7684\u4ee5\u4e3a\u8d5b\u540e\u53ef\u4ee5\u56de\u6536\u677f\u5b50\u4e86\u3002\u3002\u7ed3\u679c\u5176\u5b9e\u6253\u5f00\u4e00\u770b\u8fd8\u662f\u9648\u9e3f\u7b97\u6cd5\u3002\u3002\u3002\u3002<\/p>\n<div>\n<a href=\"https:\/\/www.shuizilong.com\/house\/wp-content\/uploads\/2013\/01\/123.jpg\"><img loading=\"lazy\" decoding=\"async\" data-attachment-id=\"642\" data-permalink=\"https:\/\/www.shuizilong.com\/house\/archives\/codechef-january-challenge-2013\/123-2\/\" data-orig-file=\"https:\/\/www.shuizilong.com\/house\/wp-content\/uploads\/2013\/01\/123.jpg\" data-orig-size=\"496,437\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;}\" data-image-title=\"123\" data-image-description=\"\" data-image-caption=\"\" data-medium-file=\"https:\/\/www.shuizilong.com\/house\/wp-content\/uploads\/2013\/01\/123-300x264.jpg\" data-large-file=\"https:\/\/www.shuizilong.com\/house\/wp-content\/uploads\/2013\/01\/123.jpg\" src=\"https:\/\/www.shuizilong.com\/house\/wp-content\/uploads\/2013\/01\/123.jpg\" alt=\"123\" width=\"496\" height=\"437\" class=\"aligncenter size-full wp-image-642\" srcset=\"https:\/\/www.shuizilong.com\/house\/wp-content\/uploads\/2013\/01\/123.jpg 496w, https:\/\/www.shuizilong.com\/house\/wp-content\/uploads\/2013\/01\/123-300x264.jpg 300w, https:\/\/www.shuizilong.com\/house\/wp-content\/uploads\/2013\/01\/123-340x300.jpg 340w\" sizes=\"auto, (max-width: 496px) 100vw, 496px\" \/><\/a> <a href=\"https:\/\/www.shuizilong.com\/house\/wp-content\/uploads\/2013\/01\/234.jpg\"><img loading=\"lazy\" decoding=\"async\" data-attachment-id=\"643\" data-permalink=\"https:\/\/www.shuizilong.com\/house\/archives\/codechef-january-challenge-2013\/attachment\/234\/\" data-orig-file=\"https:\/\/www.shuizilong.com\/house\/wp-content\/uploads\/2013\/01\/234.jpg\" data-orig-size=\"455,432\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;}\" data-image-title=\"234\" data-image-description=\"\" data-image-caption=\"\" data-medium-file=\"https:\/\/www.shuizilong.com\/house\/wp-content\/uploads\/2013\/01\/234-300x284.jpg\" data-large-file=\"https:\/\/www.shuizilong.com\/house\/wp-content\/uploads\/2013\/01\/234.jpg\" src=\"https:\/\/www.shuizilong.com\/house\/wp-content\/uploads\/2013\/01\/234.jpg\" alt=\"234\" width=\"455\" height=\"432\" class=\"aligncenter size-full wp-image-643\" srcset=\"https:\/\/www.shuizilong.com\/house\/wp-content\/uploads\/2013\/01\/234.jpg 455w, https:\/\/www.shuizilong.com\/house\/wp-content\/uploads\/2013\/01\/234-300x284.jpg 300w, https:\/\/www.shuizilong.com\/house\/wp-content\/uploads\/2013\/01\/234-315x300.jpg 315w\" sizes=\"auto, (max-width: 455px) 100vw, 455px\" \/><\/a><\/p>\n<\/div>\n<p>\u3002\u3002\u8003\u5bdf\u5706\u4e0e\u8fb9\u754c\u76f8\u4ea4\u7684\u60c5\u51b5\u3002\u3002\u53f3\u8fb9\u754c\u7684\u60c5\u51b5\u57fa\u7ebf alpha \u662f 0 \u3002\u3002\u65cb\u8f6c\u89d2 beta \u9700\u8981\u4f7f\u7528 acos \u8ba1\u7b97\u51fa\u6765\u3002\u3002<br \/>\n\u3002\u3002\u3002\u4e24\u4e2a\u533a\u95f4\u5206\u522b alpha &#8211; beta \u548c alpha + beta\u3002\u3002<br \/>\n\u3002\u8fd9\u91cc\u8981\u5206\u5728\u77e9\u5f62\u5185\u90e8\u548c\u5916\u90e8\u4e24\u79cd\u60c5\u51b5\u8ba8\u8bba\u4e00\u4e0b\u3002\u3002\u5bf9\u4e8e\u540e\u8005\u3002\u3002\u57fa\u7ebf\u8981\u53d6\u5bf9\u79f0\u4f4d\u7f6e\u3002\u3002beta \u8981\u53d6\u8d1f\u3002\u3002\u3002<\/p>\n<p>\u3002\u3002\u3002\u3002\u8d5b\u540e\u53d1\u73b0\u5176\u5b9e\u4e5f\u53ef\u4ee5\u4e0d\u8ba8\u8bba\u3002\u3002\u56e0\u4e3a acos \u5728\u8d1f\u6570\u7684\u60c5\u51b5\u4e0b\u53ef\u4ee5\u8fd4\u56de\u949d\u89d2\u3002\u3002\u3002<br \/>\n\u3002\u3002\u7136\u540e\u6211\u6539\u6389\u8fd9\u4e2a\u591a\u4f59\u7684\u8ba8\u8bba\u5c31 A \u4e86\u3002\u3002\u3002<\/p>\n<p>\u3002\u3002\u3002\u5c3c\u739b\u4e00\u53e3\u8840\u5c31\u55b7\u5c4f\u5e55\u4e0a\u4e86\u554a\u3002\u3002\u3002\u6211\u77e5\u9053\u6211\u662f\u5199\u4e11\u4e86\u3002\u3002\u4f46\u662f\u8c01\u80fd\u544a\u8bc9\u6211\u8fd9\u4e24\u4e2a\u4e0d\u662f\u7b49\u4ef7\u7684\u5417\u3002\u3002\u3002\u3002<br \/>\n<del>(\u4ee3\u7801\u53d1<a href=\"http:\/\/discuss.codechef.com\/questions\/5151\/andoor-editorial?sort=votes&#038;page=2\">\u8ba8\u8bba\u7248<\/a>\u4e86\u3002\u3002\u6c42 debug \u3002\u3002\u3002<\/del><\/p>\n<p>&#8211;UPD&#8211;<br \/>\n\u3002\u3002Bug \u627e\u5230\u4e86\u3002\uff08\u3002\u4e4b\u524d Outcross() \u51fd\u6570\u5728\u67d0\u79cd\u60c5\u51b5\u4e0b\u4f1a\u7206\u9519\u3001\u3001\u3001 \/$:o~o<br \/>\n\u6539\u6b63\u540e\u7684\u4ee3\u7801\u3002\u3002<a href=\"http:\/\/www.codechef.com\/viewsolution\/1745463\">\u3002\u5e26\u8ba8\u8bba\u3002\u3002<\/a>..<a href=\"http:\/\/www.codechef.com\/viewsolution\/1745467\">\u3002\u4e0d\u5e26\u8ba8\u8bba\u3002\u3002<\/a>\u3002<\/p>\n<h2 style=\"color: #7B5E47;\">Level 3. Cucumber Boy and Cucumber Girl<\/h2>\n<h3>Brief description:<\/h3>\n<p>\u3002\u3002\u7ed9\u5b9a nn \u4e2a n \u9636\u65b9\u9635 A\u3002\u3002\u8003\u5bdf\u6bcf\u5bf9\u65b9\u9635\u4e58\u79ef\u77e9\u9635 D = Ai * Aj | 0 <= i < j < nn \u3002\u3002\n\u3002\u3002\u5bf9\u4e8e\u6bcf\u4e2a\u6392\u5217 P\u3002\u3002\u8bb0 tr(P) \u4e3a\u6240\u6709 D[i][Pi] \u4e2d\uff0c\u662f\u5426\u6709\u4e00\u9879\u662f\u5947\u6570\u3002\u3002\u3002\n\u3002\u3002\u8bb0 cnt(D) \u4e3a\u6240\u6709 tr \u7684\u548c\u7684\u5947\u5076\u6027\u3002\u3002\u3002\u6c42\u6240\u6709 cnt(D) \u7684\u548c\u3002\u3002\n\n\n\n<h3>Analysis:<\/h3>\n<p>&#8230; \u5f88\u5bb9\u6613\u53d1\u73b0 cnt(D) \u5176\u5b9e\u7b49\u4ef7\u4e8e\u5176\u5bf9\u5e94\u7684\u79ef\u548c\u5f0f % 2 \u7684\u4f59\u6570\u3002\u3002\uff08 perm(D) % 2\u3002\u3002<br \/>\n\u3002\u3002\u800c perm(D) == det(D) (mod 2)\u3002\u3002\u56e0\u6b64\u8f6c\u6362\u4e3a\u76f8\u5e94\u77e9\u9635\u7684\u884c\u5217\u5f0f\u3002\u3002<br \/>\n\uff08\u3002\u3002\u65b9\u6cd5\u662f\u6539\u53d8 D \u77e9\u9635\u6bcf\u4e00\u9879\u7684\u5947\u5076\u6027\u3002\u3002\u8fd9\u6837\u662f\u5b58\u5728\u5947\u6570\u3002\u3002\u5c31\u53d8\u6210\u4e86\u5bf9\u5e94\u7684\u79ef\u548c\u5f0f\u7684\u4e58\u79ef\u662f\u5426\u4e3a 0 \u3002\u3002\u3002<br \/>\n\uff08\u3002\u3002\u800c\u4fee\u6539\u540e\u7684\u77e9\u9635\u3002\u3002\u53ef\u4ee5\u901a\u8fc7\u5bf9 A \u77e9\u9635\u589e\u52a0\u4e00\u5217\u5168\u662f 1 \u7684\u5143\u7d20\u6765\u5f97\u5230\u3002\u3002<\/p>\n<p>\u3002\u3002\u5bf9\u4e8e perm(D) % 2 \u3002\u8fd9\u4e2a\u662f\u8001\u5957\u8def\u4e86\u3002\u3002\u76ee\u524d\u505a\u5230\u7684\u5927\u90e8\u5206\u5173\u4e8e\u79ef\u548c\u5f0f\u7684\u9898\u76ee\u3002\u3002<a href=\"https:\/\/www.shuizilong.com\/house\/archives\/%E3%80%90%E7%AC%AC%E5%9B%9B%E6%AC%A1-acdream-%E7%BE%A4%E5%8E%9F%E5%88%9B%E7%BE%A4%E8%B5%9B%E3%80%91%E8%A7%A3%E9%A2%98%E6%8A%A5%E5%91%8A\/\">\u90fd\u5f52\u4e8e\u4e86\u8fd9\u79cd\u5f62\u5f0f\u3002\u3002<\/a>\uff08\u3002\u3002\u6c42 perm(D) % 2^k \u600e\u4e48\u505a\uff1f\u3002\u3002<br \/>\n\u3002\u3002\u7531\u6b64\u53ef\u4ee5\u5f97\u5230\u4e00\u4e2a O(nn^2 n^3) \u7684\u7b97\u6cd5 \u3002\u3002<\/p>\n<p>&#8230; \u6bd4\u8d5b\u7684\u65f6\u5019\u5c31\u4e00\u76f4\u5361\u5728\u8fd9\u4e00\u6b65\u4e86\u3002\u3002<br \/>\n\u3002\u3002\u8bfb\u4e86\u4e00\u4e0b<a href=\"http:\/\/discuss.codechef.com\/questions\/5293\/cucumber-editorial\">\u9898\u89e3<\/a>\u3002\u3002\u53d1\u73b0\u540e\u9762\u9700\u8981\u7528\u3002\u3002<a href=\"Cauchy\u2013Binet formula\">Cauchy\u2013Binet formula<\/a><br \/>\n\u3002\u3002\u4e5f\u5c31\u662f\u5c06\u4e24\u4e2a\u77e9\u9635\u4e58\u79ef\u7684\u884c\u5217\u5f0f\u3002\u3002\u5206\u89e3\u4e3a n \u4e2a\u5bf9\u5e94\u7684\u4f59\u5b50\u5f0f\u7684\u4e58\u79ef\u3002\u3002\u3002<\/p>\n<p>\u3002\u3002\u3002\u7531\u4e8e\u6211\u4eec\u53ea\u9700\u8981\u5f97\u5230\u5947\u5076\u6027\u3002\u3002\u6574\u4e2a\u6c42\u884c\u5217\u5f0f\u7684\u8fc7\u7a0b\u548c\u5206\u89e3\u4ee5\u53ca\u7ec4\u5408\u7684\u8fc7\u7a0b\u3002\u3002\u90fd\u53ef\u4ee5\u901a\u8fc7\u4f4d\u8fd0\u7b97\u4f18\u5316\u4e00\u7ef4\u3002\u3002\u3002<br \/>\n\u3002\u3002\u6240\u4ee5\u6700\u540e\u590d\u6742\u5ea6\u662f O(nn^2 + nn*n^2)\u3002\u3002<\/p>\n<h2 style=\"color: #7B5E47;\">Level 4. A Fence for Byteland<\/h2>\n<h3>Brief description: <\/h3>\n<p>&#8230; \u7ed9\u5b9a\u4e24\u7ec4\u70b9\u96c6\u3002\u3002\u6c42\u4e00\u4e2a\u7b80\u5355\u591a\u8fb9\u5f62\u3002\u3002\u5212\u5206\u5f00\u4e24\u7ec4\u70b9\u96c6\u3002\u3002<br \/>\n\u3002\uff08\u5141\u8bb8\u70b9\u5728\u591a\u8fb9\u5f62\u4e0a\u3002\u3002\u8fd9\u79cd\u60c5\u51b5\u4e0b\u7b97\u76f8\u5f53\u4e8e\u5220\u9664\u8fd9\u4e2a\u70b9\u3002\u3002\u3002<\/p>\n<h3>Analysis: <\/h3>\n<p>&#8230; \u7b2c\u4e00\u53cd\u5e94\u662f\u6b27\u51e0\u91cc\u5f97 TSP \u8fd1\u4f3c\u7b97\u6cd5\u3002\u3002\u3002\u540e\u6765\u56e0\u4e3a\u5706\u5e76\u5361\u7684\u592a\u4e45\u3002\u3002\u5c31\u5199\u4e86\u4e2a\u591a\u8fb9\u5f62\u8986\u76d6\u6240\u6709\u70b9\u7684\u6e23\u6e23\u7b97\u6cd5\u4ea4\u4e0a\u53bb\u4e86\u3001\u3001\u3001\u592a\u6ca1\u8ffd\u6c42\u4e86\u3002\uff01\uff01\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>http:\/\/www.codechef.com\/JAN13\/<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","enabled":false}}},"categories":[83],"tags":[],"class_list":["post-640","post","type-post","status-publish","format-standard","hentry","category-codechef"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/p2tdP7-ak","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/posts\/640","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/comments?post=640"}],"version-history":[{"count":1,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/posts\/640\/revisions"}],"predecessor-version":[{"id":641,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/posts\/640\/revisions\/641"}],"wp:attachment":[{"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/media?parent=640"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/categories?post=640"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/tags?post=640"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}