{"id":329,"date":"2018-07-24T07:43:08","date_gmt":"2018-07-24T07:43:08","guid":{"rendered":"https:\/\/www.haoyuan.info\/?p=329"},"modified":"2018-07-24T14:48:13","modified_gmt":"2018-07-24T14:48:13","slug":"%e8%af%8d%e9%9f%b5","status":"publish","type":"post","link":"https:\/\/haoyuan.info\/?p=329","title":{"rendered":"UPC6360 \u8bcd\u97f5 2018\u5317\u4eac\u51ac\u4ee4\u8425"},"content":{"rendered":"

\u9898\u76ee\u63cf\u8ff0<\/h3>\n

Adrian \u5f88\u559c\u6b22\u8bd7\u6b4c\u4e2d\u7684\u97f5\u3002\u4ed6\u8ba4\u4e3a\uff0c\u4e24\u4e2a\u5355\u8bcd\u62bc\u97f5\u5f53\u4e14\u4ec5\u5f53\u5b83\u4eec\u7684\u6700\u957f\u516c\u5171 \u540e\u7f00\u7684\u957f\u5ea6\u81f3\u5c11\u662f\u5176\u4e2d\u8f83\u957f\u5355\u8bcd\u7684\u957f\u5ea6\u51cf\u4e00\u3002\u4e5f\u5c31\u662f\u8bf4\uff0c\u5355\u8bcd A \u4e0e\u5355\u8bcd B \u62bc\u97f5 \u5f53\u4e14\u4ec5\u5f53 LCS(A, B) \u2265 max(|A|, |B|) \u2013 1\u3002\uff08\u5176\u4e2d LCS \u662f\u6700\u957f\u516c\u5171\u540e\u7f00 longest common suffix \u7684\u7f29\u5199\uff09
\n\u73b0\u5728\uff0cAdrian \u5f97\u5230\u4e86 N \u4e2a\u5355\u8bcd\u3002\u4ed6\u60f3\u4ece\u4e2d\u9009\u51fa\u5c3d\u53ef\u80fd\u591a\u7684\u5355\u8bcd\uff0c\u8981\u6c42\u5b83\u4eec\u80fd \u7ec4\u6210\u4e00\u4e2a\u5355\u8bcd\u5e8f\u5217\uff0c\u4f7f\u5f97\u5355\u8bcd\u5e8f\u5217\u4e2d\u4efb\u4f55\u4e24\u4e2a\u76f8\u90bb\u5355\u8bcd\u662f\u62bc\u97f5\u7684\u3002<\/p>\n

\u8f93\u5165<\/h3>\n

\u7b2c\u4e00\u884c\u662f\u4e00\u4e2a\u6574\u6570N\u3002
\n\u63a5\u4e0b\u6765N\u884c\uff0c\u6bcf\u884c\u4e00\u4e2a\u7531\u5c0f\u5199\u82f1\u6587\u5b57\u6bcd\u7ec4\u6210\u7684\u5b57\u7b26\u4e32\uff0c\u8868\u793a\u6bcf\u4e2a\u5355\u8bcd\u3002\u6240\u6709\u5355\u8bcd\u4e92\u4e0d\u76f8\u540c\u3002<\/p>\n

\u8f93\u51fa<\/h3>\n

\u8f93\u51fa\u4e00\u884c\uff0c\u4e3a\u4e00\u4e2a\u6574\u6570\uff0c\u8868\u793a\u6700\u957f\u5355\u8bcd\u5e8f\u5217\u7684\u957f\u5ea6\u3002<\/p>\n

\u9898\u89e3<\/h2>\n

\u9996\u5148\u770b\u5230LCS\u53ef\u4ee5\u8003\u8651\u5bf9\u5b57\u7b26\u4e32\u9006\u5e8f\u5efa\u7acbTrie\u6811\uff0c\u5173\u952e\u5728\u4e8e\u600e\u4e48\u5bf9\u4e8e\u8fd9\u68f5\u6811\u600e\u4e48\u5904\u7406\u51fa\u6700\u957f\u94fe\u3002
\n\u9996\u5148\u6211\u4eec\u77e5\u9053\u8bbe\u6811\u4e0a\u67d0\u4e2a\u8282\u70b9x\u4f5c\u4e3a\u6839\u8282\u70b9\uff0c\u5bf9\u4e8e\u8fd9\u4e2a\u8282\u70b9\u6784\u9020\u51fa\u7684\u6700\u5927\u5355\u8bcd\u5e8f\u5217\u7684\u89e3ans\uff0c\u5e94\u8be5\u4e3a
\n\u8bbe\u4ee5x\u4e3a\u6839\u7684\u6700\u957f\u94fe\u4e3af[x]\uff0c\u6b21\u957f\u94fe\u4e3ag[x],\u4ee5x\u4e3a\u6839\u7684\u5b69\u5b50\u8282\u70b9\u4e3ason[x]
\n\u5219ans = f[x] + g[x] + son[x] + word_end[x] – 2
\n\u4ece\u5b57\u7b26\u4e32\u7ed3\u675f\u4f4d\u7f6e\u8fdb\u884c\u6811\u5f62dp\u5373\u53ef<\/p>\n

\u4ee3\u7801<\/h2>\n

C\/C++<\/h4>\n
#include <iostream>\n#include <cstring>\n#include <algorithm>\n\nusing namespace std;\nconst int maxn = 3e6 + 1e2;\n\nint sum, f[maxn], g[maxn];\nint head[maxn], pcnt = 1, ecnt;\nstruct Node {\n    int num, next;\n} edges[maxn];\n\nvoid addEdge(int s, int e) {\n    edges[++ecnt].num = e;\n    edges[ecnt].next = head[s];\n    head[s] = ecnt;\n}\n\nint fa[maxn], sons[maxn], val[maxn];\nbool word_end[maxn];\nstring s;\n\nvoid trie(const string::reverse_iterator &b, string::reverse_iterator e) {\n    int root = 1;\n    auto iter = b;\n    for (; iter != e; ++iter) {\n        bool flag = true;\n        auto w = *iter - 'a' + 1;\n        for (int i = head[root]; i && flag; i = edges[i].next) {\n            if (val[edges[i].num] == w) {\n                root = edges[i].num;\n                flag = false;\n            }\n        }\n        if (flag) break;\n    }\n    for (; iter != e; ++iter) {\n        f[pcnt] = g[pcnt] = 1;\n        val[++pcnt] = *iter - 'a' + 1;\n        addEdge(root, pcnt);\n        fa[pcnt] = root;\n        root = pcnt;\n    }\n    word_end[root] = true;\n    sons[fa[root]]++;\n}\n\n\nint main() {\n    ios::sync_with_stdio(false);\n    cin.tie(nullptr);\n    int T;\n    cin >> T;\n    while (T--) {\n        cin >> s;\n        trie(s.rbegin(), s.rend());\n    }\n    for (int i = pcnt; i; --i)\n        if (word_end[i]) {\n            if (f[fa[i]] < f[i] + sons[i]) {\n                g[fa[i]] = f[fa[i]];\n                f[fa[i]] = f[i] + sons[i];\n            } else g[fa[i]] = max(g[fa[i]], f[i] + sons[i]);\n        }\n    for (int i = pcnt; i; --i) {\n        sum = max(sum, f[i] + g[i] + sons[i] + word_end[i] - 2);\n    }\n    cout << sum << \"\\n\";\n}\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"
\u9898\u76ee\u63cf\u8ff0 Adrian \u5f88\u559c\u6b22\u8bd7\u6b4c\u4e2d\u7684\u97f5\u3002\u4ed6\u8ba4\u4e3a\uff0c\u4e24\u4e2a\u5355\u8bcd\u62bc\u97f5\u5f53\u4e14\u4ec5\u5f53\u5b83\u4eec\u7684\u6700\u957f\u516c\u5171 \u540e\u7f00\u7684\u957f\u5ea6\u81f3\u5c11\u662f\u5176\u4e2d\u8f83\u957f […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"spay_email":"","footnotes":"","jetpack_publicize_message":"","jetpack_is_tweetstorm":false},"categories":[39,43,25,42,22],"tags":[],"class_list":["post-329","post","type-post","status-publish","format-standard","hentry","category-c","category-43","category-25","category-dp","category-22"],"jetpack_featured_media_url":"","jetpack_publicize_connections":[],"jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p8UC2c-5j","jetpack_likes_enabled":true,"jetpack-related-posts":[],"_links":{"self":[{"href":"https:\/\/haoyuan.info\/index.php?rest_route=\/wp\/v2\/posts\/329","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/haoyuan.info\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/haoyuan.info\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/haoyuan.info\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/haoyuan.info\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=329"}],"version-history":[{"count":4,"href":"https:\/\/haoyuan.info\/index.php?rest_route=\/wp\/v2\/posts\/329\/revisions"}],"predecessor-version":[{"id":333,"href":"https:\/\/haoyuan.info\/index.php?rest_route=\/wp\/v2\/posts\/329\/revisions\/333"}],"wp:attachment":[{"href":"https:\/\/haoyuan.info\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=329"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/haoyuan.info\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=329"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/haoyuan.info\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=329"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}