{"id":581,"date":"2012-11-22T06:54:06","date_gmt":"2012-11-21T22:54:06","guid":{"rendered":"http:\/\/www.shuizilong.com\/house\/?p=581"},"modified":"2012-11-22T07:04:50","modified_gmt":"2012-11-21T23:04:50","slug":"codeforces-round-151","status":"publish","type":"post","link":"https:\/\/www.shuizilong.com\/house\/archives\/codeforces-round-151\/","title":{"rendered":"Codeforces Round #151"},"content":{"rendered":"

\u3002\u3002\u6211\u73b0\u5728\u8fd9\u4e2a\u72b6\u6001\u771f\u662f SB \u5230\u5bb6\u4e86\u554a\u3002\u3002\u8fd9\u8981\u662f\u5728\u73b0\u573a\u8d5b\u5c31\u662f\u6012\u5356\u961f\u53cb\u4e86\u3002\u3002\u3002
\n\uff08\u3002\u3002\u3002\u8fd8\u597d DIV 2.\u3002\u3002\u8981\u4e0d\u7136 p \u70b9\u53c8\u6389\u4e00\u5730\u3002\u3002\u3002<\/p>\n

<\/p>\n

Problem E. Blood Cousins Return<\/h3>\n

Brief description: <\/h3>\n

\u7ed9\u5b9a\u4e00\u9897\u6709\u6839\u6811\u3001\u6bcf\u4e2a\u7ed3\u70b9\u6709\u4e00\u4e2a\u540d\u5b57\uff0c\u8be2\u95ee\u67d0\u4e2a\u7ed3\u70b9\u5f80\u4e0b k \u5c42\u6709\u591a\u5c11\u4e0d\u76f8\u540c\u7684\u540d\u5b57\u3002
\n<\/p>\n

Analysis: <\/h3>\n

\u3002\u3002\u4e0b\u9762\u4e24\u4e2a\u7b97\u6cd5\u90fd\u662f\u5728\u7ebf\u7684\u3002\u3002\u5f88\u5bb9\u6613\u63a8\u5e7f\u5230\u540d\u5b57\u53ef\u4fee\u6539\u7684\u60c5\u51b5\u3002\u3002\uff08\u3002\u3002\u4fee\u6539\u6811\u7684\u7ed3\u6784\u7684\u8bdd\u8fd8\u80fd\u505a\u4e48\uff1f\u3002<\/p>\n

\u3002\u8003\u8651\u8be2\u95ee\u7ed3\u70b9\u5fc5\u7136\u5904\u5728\u540c\u4e00\u4e2a\u5c42\u7684\u4e00\u4e2a\u533a\u95f4\u3002\u3002
\n\u3002\u56e0\u6b64\u5148 dfs \u5e8f\u3002\u3002\u7136\u540e\u5bf9\u4e8e\u67d0\u4e2a\u8be2\u95ee\u3002\u3002\u53ef\u4ee5\u4e8c\u5206\u5b9a\u4f4d\u5230\u533a\u95f4\u3002\u3002
\n\u8fd9\u6837\u5bf9\u4e8e\u6bcf\u4e00\u5c42\u5c31\u662f\u9759\u6001\u7684\u3002\u3002\u8be2\u95ee\u67d0\u4e2a\u533a\u95f4\u6709\u591a\u5c11\u4e0d\u76f8\u540c\u7684\u5143\u7d20\u3002<\/a>\u7684\u95ee\u9898\u3002\u3002\u6570\u636e\u7ed3\u6784\u7ef4\u62a4\u5373\u53ef\u3002\u3002<\/p>\n

\u3002\u3002\u3002\u6211\u731c watashi \u5927\u6982\u5c31\u662f\u8fd9\u4e48\u505a\u7684\u3002\u3002<\/a>\uff08\u7ed9 Haskell \u00d7 4 \u8dea\u70c2\uff01\u3002\u3002<\/p>\n

\u3002\u3002\u6211\u73b0\u573a\u751f\u7684\u65b9\u6cd5\u662f\u500d\u589e\u7956\u5148\u4e71\u641e\u3002\u3002\u5927\u6982\u662f\u8981\u53cd\u8fc7\u6765\u518d\u7ef4\u62a4\u51fa\u4e00\u4e2a \u201c\u500d\u589e\u5b69\u5b50 \u5217\u8868\u7684\u4e1c\u897f\u3002\u3002
\n\u3002\u56e0\u4e3a\u8fd9\u6837\u662f\u4e00\u5bf9\u591a\u3002\u3002\u6240\u4ee5\u5c31\u53ef\u80fd\u5bfc\u81f4\u4e2d\u95f4 dfs() \u4e0b\u53bb\u7684\u65f6\u5019\u4f1a\u540c\u65f6\u5904\u5728\u597d\u591a\u4e2a\u72b6\u6001\u3002\u3002\u7ed3\u679c\u6211\u5c31 TLE \u4e86\u3002\u3002\u3002<\/p>\n

\u6700\u574f\u60c5\u51b5\u662f\u5b8c\u5168\u4e8c\u53c9\u6811\u3002\u3002\u6bcf\u6b21\u8be2\u95ee\u6700\u5e95\u5c42\u7684\u53f6\u5b50\u3002\u3002\u5219\u6bcf\u6b21\u7684\u590d\u6742\u5ea6\u90fd\u662f O(n) \u7684\u3002\u3002\u3002\u3002<\/p>\n

\u3002\u3002\u8d5b\u540e\u770b\u4e86\u4e00\u4e0b rng_58 \u7684\u4ee3\u7801<\/a>\u3002\u3002\u53d1\u73b0\u5b83\u4e8c\u5206\u5b9a\u4f4d\u5b8c\u533a\u95f4\u4ee5\u540e\u662f\u66b4\u529b\u7684\u3002\u3002\u3002\u3002\u3002\u3002
\n\u3002\u3002\u3002\u518d\u4ed4\u7ec6\u770b\u4e86\u4e00\u4e0b\u597d\u50cf\u8bb0\u5f55\u4e86\u4e00\u4e0b\u6bcf\u6b21\u8be2\u95ee\u7684\u7b54\u6848\u3002\u3002\u9047\u5230\u76f8\u540c\u8be2\u95ee\u5c31\u4e0d\u518d\u505a\u4e86\u3002\u3002
\n\u3002\u3002\u7136\u540e\u6211\u628a\u8fd9\u4e2a\u4e5f\u52a0\u4e0a\u3002\u3002\u5c31\u8fc7\u4e86\u3002\u3002= =\uff08\u5e38\u6570\u5927\u4e86\u70b9\u3002\u3002\u4ed4\u7ec6\u60f3\u4e00\u4e0b\u7684\u8bdd\u5176\u5b9e\u8fd9\u4e00\u6b65\u5f88\u79d1\u5b66\u3002\u3002\u56e0\u4e3a\u590d\u6742\u5ea6\u662f O(n) \u7684\u8be2\u95ee\u4e0d\u4f1a\u8d85\u8fc7 O(log(n)) \u4e2a\u3002\u3002\u3002<\/p>\n

http:\/\/codeforces.com\/contest\/246\/submission\/2623278<\/a><\/p>\n

\r\n\/* .................................................................................................................................. *\/\r\n\r\nconst int N = 100009, L = 19;\r\n\r\ntypedef bitset<N> mask;\r\n\r\nchar buf[25]; VI adj[N], son[N][L]; MSI H; MPIII M;\r\nint p[N][L], id[N], m, n; mask res;\r\n\r\n#define v son[u][lv][i]\r\nvoid dfs(int u, int k){ \/\/ \u56de\u7b54\u8be2\u95ee\u3002\u3002\u3002\r\n    if (!k) res.set(id[u]);\r\n    else{\r\n        int lv = low_idx(k) - 1, d = low_bit(k);\r\n        REP(i, SZ(son[u][lv])) dfs(v, k-d);\r\n\r\n    }\r\n}\r\n#undef v\r\n#define v adj[u][i]\r\nvoid gao(int u = 0){ \/\/ \u500d\u589e\u7956\u5148\u3002\u3002\u9884\u5904\u7406\u3002\u3002\r\n    REP(i, SZ(adj[u])){\r\n        p[v][0] = u, son[u][0].PB(v); FOR(lv, 1, L){\r\n            p[v][lv] = p[p[v][lv-1]][lv-1];\r\n            if (!p[v][lv]) break;\r\n            son[p[v][lv]][lv].PB(v);\r\n        }\r\n        gao(v);\r\n    }\r\n}\r\n\r\nint main(){\r\n\r\n#ifndef ONLINE_JUDGE\r\n    freopen("in.txt", "r", stdin);\r\n#endif\r\n\r\n    string s; REP_1_C(i, RD(n)){\r\n        RS(buf), s = buf; if (!CTN(H, s)) H[s] = m++;\r\n        id[i] = H[s]; int p; RD(p);\r\n        adj[p].PB(i);\r\n    }\r\n\r\n    gao();\r\n\r\n    Rush{\r\n        int u, k; RD(u, k); if (!M[MP(u, k)]){\r\n            res.reset(), dfs(u, k);\r\n            M[MP(u, k)] = res.count();\r\n        }\r\n        OT(M[MP(u, k)]);\r\n    }\r\n}\r\n<\/pre>\n
External link: <\/h3>\n","protected":false},"excerpt":{"rendered":"
\u3002\u3002\u6211\u73b0\u5728\u8fd9\u4e2a\u72b6\u6001\u771f\u662f SB \u5230\u5bb6\u4e86\u554a\u3002\u3002\u8fd9\u8981\u662f\u5728\u73b0\u573a\u8d5b\u5c31\u662f\u6012\u5356\u961f\u53cb\u4e86\u3002\u3002\u3002 \uff08\u3002\u3002\u3002\u8fd8\u597d DIV 2.\u3002\u3002\u8981\u4e0d\u7136 p \u70b9\u53c8\u6389\u4e00\u5730\u3002\u3002\u3002<\/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":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","enabled":false}}},"categories":[18],"tags":[],"class_list":["post-581","post","type-post","status-publish","format-standard","hentry","category-codeforces"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/p2tdP7-9n","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/posts\/581","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=581"}],"version-history":[{"count":0,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/posts\/581\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/media?parent=581"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/categories?post=581"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.shuizilong.com\/house\/wp-json\/wp\/v2\/tags?post=581"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}