{"id":1045,"date":"2025-05-09T01:03:15","date_gmt":"2025-05-08T17:03:15","guid":{"rendered":"https:\/\/beijian99.top\/?p=1045"},"modified":"2025-05-10T09:05:56","modified_gmt":"2025-05-10T01:05:56","slug":"%e6%b4%97%e7%89%8c%e7%ae%97%e6%b3%95%ef%bc%88shuffling-algorithm%ef%bc%89","status":"publish","type":"post","link":"https:\/\/beijian99.top\/?p=1045","title":{"rendered":"\u6d17\u724c\u7b97\u6cd5\uff08Shuffling Algorithm\uff09"},"content":{"rendered":"\n
\n

\u6d17\u724c\u7b97\u6cd5\uff08Shuffling Algorithm\uff09\u662f\u8ba1\u7b97\u673a\u79d1\u5b66\u4e2d\u7528\u4e8e\u968f\u673a\u6392\u5217\u4e00\u7ec4\u5143\u7d20\u987a\u5e8f\u7684\u7b97\u6cd5\u3002\u5b83\u5728\u6e38\u620f\u5f00\u53d1\u3001\u6570\u636e\u5206\u6790\u3001\u5bc6\u7801\u5b66\u7b49\u9886\u57df\u6709\u7740\u5e7f\u6cdb\u5e94\u7528\u3002<\/p>\n<\/blockquote>\n\n\n\n

\"\"<\/figure>\n\n\n\n

1.\u6d17\u724c\u7b97\u6cd5\u6982\u8ff0<\/strong><\/h4>\n\n\n\n

\u6d17\u724c\u7b97\u6cd5\u7684\u6838\u5fc3\u76ee\u6807\u662f\u5c06\u4e00\u4e2a\u5e8f\u5217\u4e2d\u7684\u5143\u7d20\u968f\u673a\u91cd\u65b0\u6392\u5217\uff0c\u4f7f\u5f97\u6bcf\u4e2a\u5143\u7d20\u51fa\u73b0\u5728\u6bcf\u4e2a\u4f4d\u7f6e\u7684\u6982\u7387\u76f8\u7b49\u3002\u4e00\u4e2a\u826f\u597d\u7684\u6d17\u724c\u7b97\u6cd5\u5e94\u8be5\u6ee1\u8db3\uff1a<\/p>\n\n\n\n

    \n
  1. \u5747\u5300\u6027\uff1a\u6240\u6709\u53ef\u80fd\u7684\u6392\u5217\u51fa\u73b0\u7684\u6982\u7387\u76f8\u7b49<\/li>\n\n\n\n
  2. \u65e0\u504f\u6027\uff1a\u7b97\u6cd5\u672c\u8eab\u4e0d\u5f15\u5165\u4efb\u4f55\u504f\u5dee<\/li>\n\n\n\n
  3. \u9ad8\u6548\u6027\uff1a\u65f6\u95f4\u590d\u6742\u5ea6\u5c3d\u53ef\u80fd\u4f4e<\/li>\n\n\n\n
  4. Fisher-Yates\u6d17\u724c\u7b97\u6cd5<\/li>\n<\/ol>\n\n\n\n

    \u6700\u7ecf\u5178\u7684\u6d17\u724c\u7b97\u6cd5\u662fFisher-Yates\u7b97\u6cd5\uff0c\u7531Ronald Fisher\u548cFrank Yates\u4e8e1938\u5e74\u63d0\u51fa\uff0c\u540e\u7531Donald Knuth\u6539\u8fdb\u4e3a\u73b0\u4ee3\u7248\u672c\u3002<\/p>\n\n\n\n

    \u7b97\u6cd5\u6b65\u9aa4<\/strong><\/p>\n\n\n\n

      \n
    1. \u4ece\u6700\u540e\u4e00\u4e2a\u5143\u7d20\u5f00\u59cb\uff0c\u5411\u524d\u904d\u5386<\/li>\n\n\n\n
    2. \u5bf9\u4e8e\u5f53\u524d\u4f4d\u7f6ei\uff0c\u968f\u673a\u9009\u62e9\u4e00\u4e2a0\u5230i\u4e4b\u95f4\u7684\u6574\u6570j<\/li>\n\n\n\n
    3. \u4ea4\u6362\u4f4d\u7f6ei\u548c\u4f4d\u7f6ej\u7684\u5143\u7d20<\/li>\n\n\n\n
    4. \u91cd\u590d\u4e0a\u8ff0\u6b65\u9aa4\u76f4\u5230\u904d\u5386\u5b8c\u6240\u6709\u5143\u7d20<\/li>\n<\/ol>\n\n\n\n

      \u7b97\u6cd5\u7279\u70b9<\/strong><\/p>\n\n\n\n

      \u2022 \u65f6\u95f4\u590d\u6742\u5ea6\uff1aO(n)<\/p>\n\n\n\n

      \u2022 \u7a7a\u95f4\u590d\u6742\u5ea6\uff1aO(1)\uff08\u539f\u5730\u6392\u5e8f\uff09<\/p>\n\n\n\n

      \u2022 \u4fdd\u8bc1\u6bcf\u4e2a\u6392\u5217\u51fa\u73b0\u7684\u6982\u7387\u76f8\u540c<\/p>\n\n\n\n

      2.Go\u8bed\u8a00\u4e2d\u7684\u5b9e\u73b0<\/strong><\/h4>\n\n\n\n

      Go\u8bed\u8a00\u6807\u51c6\u5e93\u5728math\/rand<\/code>\u5305\u4e2d\u63d0\u4f9b\u4e86Perm<\/code>\u51fd\u6570\u6765\u751f\u6210\u968f\u673a\u6392\u5217\u3002<\/p>\n\n\n\n

      2.1 rand.Perm<\/code>\u51fd\u6570<\/p>\n\n\n

      \n\/\/ Perm returns, as a slice of n ints, a pseudo-random permutation of the integers [0,n).\nfunc (r *Rand) Perm(n int) []int {\n    m := make([]int, n)\n    for i := 0; i < n; i++ {\n        j := r.Intn(i + 1)\n        m[i] = m[j]\n        m[j] = i\n    }\n    return m\n}\n<\/pre><\/div>\n\n\n
      2.2 \u5b9e\u73b0\u5206\u6790<\/strong><\/p>\n\n\n\n
        \n
      1. \u521d\u59cb\u5316\uff1a\u521b\u5efa\u4e00\u4e2a\u957f\u5ea6\u4e3an\u7684\u5207\u7247m<\/code><\/li>\n\n\n\n
      2. \u586b\u5145\u8fc7\u7a0b\uff1a
        \u2022 \u5bf9\u4e8e\u6bcf\u4e2a\u4f4d\u7f6ei\uff0c\u968f\u673a\u9009\u62e9\u4e00\u4e2a0\u5230i\u4e4b\u95f4\u7684\u4f4d\u7f6ej \u2022 \u5c06m[j]\u7684\u503c\u8d4b\u7ed9m[i] \u2022 \u5c06i\u7684\u503c\u8d4b\u7ed9m[j]<\/li>\n\n\n\n
      3. \u8fd4\u56de\u7ed3\u679c\uff1a\u6700\u7ec8\u5f97\u5230\u7684m\u5c31\u662f0\u5230n-1\u7684\u4e00\u4e2a\u968f\u673a\u6392\u5217<\/li>\n<\/ol>\n\n\n\n
        \u8fd9\u79cd\u5b9e\u73b0\u5b9e\u9645\u4e0a\u662fFisher-Yates\u7b97\u6cd5\u7684\u4e00\u79cd\u53d8\u4f53\uff0c\u79f0\u4e3a”inside-out”\u7248\u672c\uff0c\u56e0\u4e3a\u5b83\u4e0d\u9700\u8981\u9884\u5148\u586b\u5145\u6570\u7ec4\u3002<\/p>\n\n\n\n
        2.3 \u4f7f\u7528\u793a\u4f8b<\/strong><\/p>\n\n\n
        \npackage main\n\nimport (\n\t"fmt"\n\t"math\/rand"\n\t"time"\n)\n\nfunc main() {\n\t\/\/ \u521d\u59cb\u5316\u968f\u673a\u6570\u751f\u6210\u5668\n\tr := rand.New(rand.NewSource(time.Now().UnixNano()))\n\t\n\t\/\/ \u751f\u621010\u4e2a\u5143\u7d20\u7684\u968f\u673a\u6392\u5217\n\tperm := r.Perm(10)\n\tfmt.Println("Random permutation:", perm)\n\t\n\t\/\/ \u4f7f\u7528\u6392\u5217\u6765\u6253\u4e71\u5207\u7247\n\tslice := []string{"A", "B", "C", "D", "E", "F", "G", "H", "I", "J"}\n\tshuffled := make([]string, len(slice))\n\tfor i, j := range perm {\n\t\tshuffled[i] = slice[j]\n\t}\n\tfmt.Println("Shuffled slice:", shuffled)\n}\n<\/pre><\/div>\n\n\n
        3 \u5176\u4ed6\u6d17\u724c\u7b97\u6cd5\u5b9e\u73b0<\/h4>\n\n\n\n
        3.1 \u6807\u51c6Fisher-Yates\u5b9e\u73b0<\/strong><\/p>\n\n\n
        \nfunc FisherYatesShuffle(slice []int) {\n\tr := rand.New(rand.NewSource(time.Now().UnixNano()))\n\tfor i := len(slice) - 1; i > 0; i-- {\n\t\tj := r.Intn(i + 1)\n\t\tslice[i], slice[j] = slice[j], slice[i]\n\t}\n}\n<\/pre><\/div>\n\n\n
        3.2 \u4f7f\u7528rand.Shuffle<\/code><\/strong><\/p>\n\n\n\n
        Go 1.10\u5f15\u5165\u4e86\u66f4\u901a\u7528\u7684Shuffle<\/code>\u51fd\u6570\uff1a<\/p>\n\n\n
        \nfunc ShuffleSlice(slice []string) {\n\tr := rand.New(rand.NewSource(time.Now().UnixNano()))\n\tr.Shuffle(len(slice), func(i, j int) {\n\t\tslice[i], slice[j] = slice[j], slice[i]\n\t})\n}\n\n<\/pre><\/div>\n\n\n
        4.\u7b97\u6cd5\u6b63\u786e\u6027<\/h4>\n\n\n\n
        \u6d17\u724c\u7b97\u6cd5\u7684\u6b63\u786e\u6027\u8bc1\u660e\u9700\u56f4\u7ed5\u201c\u6bcf\u4e2a\u5143\u7d20\u5728\u6240\u6709\u4f4d\u7f6e\u51fa\u73b0\u7684\u6982\u7387\u5747\u7b49\u201d<\/p>\n\n\n\n
        \u6570\u5b66\u5f52\u7eb3\u6cd5\u8bc1\u660e<\/strong><\/p>\n\n\n\n
          \n
        •  \u57fa\u7840\u60c5\u5f62\u200b<\/strong>\u200b\n
            \n
          • \u5f53\u6570\u7ec4\u957f\u5ea6\u4e3a1\u65f6\uff08n=1\uff09\uff0c\u5143\u7d20\u552f\u4e00\u7684\u4f4d\u7f6e\u6982\u7387\u4e3a1\/1=1\uff0c\u663e\u7136\u6210\u7acb<\/li>\n<\/ul>\n<\/li>\n\n\n\n
          • \u200b\u200b\u5f52\u7eb3\u5047\u8bbe\u200b<\/strong>\u200b\n
              \n
            • \u200b\u200b<\/strong>\u5047\u8bbe\u5bf9\u957f\u5ea6\u4e3ak\u7684\u6570\u7ec4\u6709\u6548\uff0c\u5373\u6bcf\u4e2a\u5143\u7d20\u51fa\u73b0\u5728\u4efb\u610f\u4f4d\u7f6e\u7684\u6982\u7387\u4e3a \u200b\u200b1\/k\u200b<\/strong>\u200b<\/li>\n<\/ul>\n<\/li>\n\n\n\n
            • \u200b\u200b\u9012\u63a8\u8bc1\u660e\u200b<\/strong>\u200b\n
                \n
              • \u5f53\u6570\u7ec4\u957f\u5ea6\u4e3ak+1\u65f6\uff1a<\/li>\n\n\n\n
              • \u200b\u200b\u7b2ck+1\u6b65\u64cd\u4f5c\u200b<\/strong>\u200b\uff1a\u4ece\u533a\u95f4 \u200b\u200b[0, k]\u200b<\/strong>\u200b\u968f\u673a\u9009\u62e9\u4f4d\u7f6ej\uff0c\u4ea4\u6362arr[k]\u4e0earr[j]<\/li>\n\n\n\n
              • \u200b\u200b\u6982\u7387\u5206\u914d\u200b<\/strong>\u200b\uff1a\n
                  \n
                • \u200b\u200b\u65b0\u5143\u7d20arr[k]\u200b<\/strong>\u200b\uff1a\u88ab\u4ea4\u6362\u5230\u4efb\u610f\u4f4d\u7f6e\u7684\u6982\u7387\u4e3a \u200b\u200b1\/(k+1)\u200b<\/strong>\u200b\uff08\u56e0j\u5728k+1\u4e2a\u4f4d\u7f6e\u4e2d\u7b49\u6982\u7387\u9009\u62e9\uff09<\/li>\n\n\n\n
                • \u200b\u200b\u524dk\u4e2a\u5143\u7d20\u200b<\/strong>\u200b\uff1a\n
                    \n
                  • \u4fdd\u7559\u5728\u539f\u4f4d\u7f6e\u7684\u6982\u7387 = \u539f\u6982\u73871\/k \u00d7 \u672a\u88ab\u66ff\u6362\u7684\u6982\u7387 \u200b\u200b(1 – 1\/(k+1))\u200b<\/strong>\u200b = \u200b\u200bk\/(k+1) \u00d7 1\/k = 1\/(k+1)\u200b<\/strong>\u200b<\/li>\n\n\n\n
                  • \u88ab\u66ff\u6362\u5230\u65b0\u4f4d\u7f6ek\u7684\u6982\u7387 = \u200b\u200b1\/(k+1)\u200b<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n
                    <\/p>\n\n\n\n
                    \u8499\u7279\u5361\u7f57\u5b9e\u9a8c\u9a8c\u8bc1\uff08\u5b9e\u8df5\u68c0\u9a8c\uff09<\/strong><\/p>\n\n\n\n
                    \u901a\u8fc7\u7edf\u8ba1\u9ad8\u9891\u6b21\u6d17\u724c\u7ed3\u679c\u7684\u5206\u5e03\u6765\u8fd1\u4f3c\u9a8c\u8bc1\u6982\u7387\u5747\u7b49\u6027\uff1a<\/p>\n\n\n
                    \nfunc TestShuffleUniformity(t *testing.T) {\n\tconst (\n\t\tn         = 5      \/\/ \u5143\u7d20\u6570\u91cf\n\t\titerations = 10000 \/\/ \u6d4b\u8bd5\u6b21\u6570\n\t)\n\t\n\t\/\/ \u521d\u59cb\u5316\u7edf\u8ba1\u77e9\u9635\n\tcounts := make([][]int, n)\n\tfor i := range counts {\n\t\tcounts[i] = make([]int, n)\n\t}\n\t\n\tr := rand.New(rand.NewSource(time.Now().UnixNano()))\n\t\n\tfor k := 0; k < iterations; k++ {\n\t\tperm := r.Perm(n)\n\t\tfor pos, val := range perm {\n\t\t\tcounts[val][pos]++\n\t\t}\n\t}\n\t\n\t\/\/ \u8ba1\u7b97\u6bcf\u4e2a\u4f4d\u7f6e\u7684\u6982\u7387\n\texpected := float64(iterations) \/ float64(n)\n\ttolerance := 0.05 * expected \/\/ \u5141\u8bb85%\u7684\u504f\u5dee\n\t\n\tfor val := 0; val < n; val++ {\n\t\tfor pos := 0; pos < n; pos++ {\n\t\t\tratio := float64(counts[val][pos]) \/ expected\n\t\t\tif math.Abs(ratio-1) > tolerance {\n\t\t\t\tt.Errorf("Value %d appears in position %d %d times (%.2f%% of expected)",\n\t\t\t\t\tval, pos, counts[val][pos], ratio*100)\n\t\t\t}\n\t\t}\n\t}\n}\n\n<\/pre><\/div>\n\n\n
                    5.\u5e94\u7528\u573a\u666f<\/h4>\n\n\n\n
                      \n
                    • \u6e38\u620f\u5f00\u53d1\uff1a\u5361\u724c\u6e38\u620f\u3001\u968f\u673a\u5730\u56fe\u751f\u6210<\/li>\n\n\n\n
                    • \u673a\u5668\u5b66\u4e60\uff1a\u8bad\u7ec3\u6570\u636e\u968f\u673a\u5316<\/li>\n\n\n\n
                    • \u8d1f\u8f7d\u5747\u8861\uff1a\u8bf7\u6c42\u7684\u968f\u673a\u5206\u53d1<\/li>\n<\/ul>\n\n\n\n
                      <\/p>\n","protected":false},"excerpt":{"rendered":"
                      \u6d17\u724c\u7b97\u6cd5\uff08Shuffling Algorithm\uff09\u662f\u8ba1\u7b97\u673a\u79d1\u5b66\u4e2d\u7528\u4e8e\u968f\u673a\u6392\u5217\u4e00\u7ec4\u5143\u7d20\u987a\u5e8f\u7684\u7b97\u6cd5\u3002\u5b83\u5728\u6e38\u620f\u5f00\u53d1\u3001 […]<\/p>\n","protected":false},"author":1,"featured_media":1047,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[4],"tags":[157],"class_list":["post-1045","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-algorithm","tag-random"],"_links":{"self":[{"href":"https:\/\/beijian99.top\/index.php?rest_route=\/wp\/v2\/posts\/1045","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/beijian99.top\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/beijian99.top\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/beijian99.top\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/beijian99.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1045"}],"version-history":[{"count":4,"href":"https:\/\/beijian99.top\/index.php?rest_route=\/wp\/v2\/posts\/1045\/revisions"}],"predecessor-version":[{"id":1051,"href":"https:\/\/beijian99.top\/index.php?rest_route=\/wp\/v2\/posts\/1045\/revisions\/1051"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/beijian99.top\/index.php?rest_route=\/wp\/v2\/media\/1047"}],"wp:attachment":[{"href":"https:\/\/beijian99.top\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1045"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/beijian99.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1045"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/beijian99.top\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1045"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}