{"id":428,"date":"2019-07-29T15:30:23","date_gmt":"2019-07-29T07:30:23","guid":{"rendered":"http:\/\/47.101.202.111\/?p=428"},"modified":"2021-10-07T13:20:25","modified_gmt":"2021-10-07T05:20:25","slug":"stack-mutiple-lifo","status":"publish","type":"post","link":"http:\/\/139.196.114.170\/?p=428","title":{"rendered":"\u6808\u53ca\u53d8\u79cd – \u559c\u65b0\u538c\u65e7\u7684\u6e23\u7537"},"content":{"rendered":"

\u6808<\/h2>\n

\u5355\u8c03\u6808<\/h3>\n

PAT-A1101 \u627e\u67a2\u8f74<\/h4>\n

\u2460 \u66b4\u529b\u89e3\u6cd5\uff1a\u5206\u522b\u5411\u5de6\u53f3\u67e5\u8be2\u5927\u5c0f\u7684\u66b4\u529b\u5339\u914d $\\scriptsize O(n^2)$ \u4f1a\u8d85\u65f6
\n\u2461 \u5feb\u901f\u6392\u5e8f\u6027\u8d28\uff1a\u5de6\u4fa7\u5143\u7d20\u4e0d\u5927\u4e8e\u67a2\u8f74\uff0c\u53f3\u4fa7\u5143\u7d20\u4e0d\u5c0f\u4e8e\u67a2\u8f74\uff0c\u67a2\u8f74\u786e\u5b9a\u4e0b\u6807\u65f6\u4e3a\u6b63\u786e\u5e8f\u4e2d\u7684\u6392\u540d<\/strong>\uff0c\u6b64\u6761\u6027\u8d28\u7528\u5728TopK\u95ee\u9898\u4e2d\u88ab\u79f0\u4e3a \u5feb\u901f\u9009\u62e9\u7b97\u6cd5(Quick Select)<\/strong>\uff0c\u56e0\u6b64\u672c\u9898\u53ef\u5c06\u5e8f\u5217\u6392\u5e8f\u540e\u518d\u4e0e\u539f\u5e8f\u5217\u4e00\u4e00\u6bd4\u5bf9\uff0c\u6bd4\u5bf9\u6210\u529f\u4e14\u5bf9\u5e94\u56de\u5230\u539f\u5e8f\u5217\u5de6\u4fa7\u65e0\u66f4\u5927\u503c\u7684\u90fd\u662f\u6b63\u786e\u7684\u67a2\u8f74\u3002\u590d\u6742\u5ea6 $\\scriptsize O(nlogn)$
\n\u2462 \u6539\u7248\u5355\u8c03\u6808\uff1a\u7ebf\u6027\u95ee\u9898\u5c3d\u91cf\u5411\u4e00\u6b21\u904d\u5386\u4f18\u5316\uff0c\u8fd9\u5c31\u9700\u8981\u904d\u5386\u8fc7\u7a0b\u4e2d\u5229\u7528\u5df2\u77e5\u7ed3\u8bba\u3002\u67a2\u8f74\u7684\u6027\u8d28\u8981\u6c42\u5de6\u5c0f\u53f3\u5927\uff0c\u4e5f\u5c31\u662f\u8981\u6c42 \u6bcf\u4e2a\u5f53\u524d\u8bbf\u95ee\u6570\u90fd\u8981\u6bd4\u5df2\u8bbf\u95ee\u6570\u5927<\/strong>\uff0c\u7b26\u5408\u5355\u8c03\u6808\u6027\u8d28\u3002\u7ef4\u62a4\u4e00\u4e2a\u5355\u589e\u6808\uff0c\u53ea\u8981\u6bd4\u5df2\u77e5\u6700\u5927\u5143\u7d20\u66f4\u5927\u5c31\u5165\u6808\uff0c\u7531\u6b64\u5de6\u4fa7\u6240\u6709\u6570(\u6808\u4e2d\u5143\u7d20)\u90fd\u6bd4\u5f53\u524d\u5143\u7d20(\u6808\u9876\u5143\u7d20)\u5c0f\uff0c\u6ee1\u8db3\u4e86\u201c\u5de6\u5c0f\u6027\u8d28\u201d\u3002\u5982\u679c\u5f53\u524d\u5143\u7d20\u6bd4\u6808\u9876\u5c0f\uff0c\u8bf4\u660e\uff1aa)\u8be5\u6570\u4e0d\u6ee1\u8db3\u201c\u5de6\u5c0f\u201d\u4e0d\u5165\u6808 b)\u6808\u4e2d\u6240\u6709\u6bd4\u5f53\u524d\u5143\u7d20\u5927\u7684\u5143\u7d20\u90fd\u4e0d\u6ee1\u8db3\u201c\u53f3\u5927\u201d\u6027\u8d28\uff0c\u9700\u8981\u5c06\u5176\u4e00\u4e00\u51fa\u6808\u3002\u5982\u4f8b $\\scriptsize [1,3,4,2,5]$\uff0c\u8bfb\u5230\u6570 $\\scriptsize 2$ \u65f6\uff0c$\\scriptsize 3\u30014\u30012$ \u5747\u4e0d\u6ee1\u8db3\u6027\u8d28\uff0c\u800c $\\scriptsize 1$ \u6ee1\u8db3\u8981\u4fdd\u7559\u3002\u6700\u574f\u60c5\u51b5 $\\scriptsize n-1$ \u4e2a\u5143\u7d20\u90fd\u8981\u8fdb\u4e00\u6b21\u6808\u3001\u9000\u4e00\u6b21\u6808\uff0c\u590d\u6742\u5ea6\u4e3a $\\scriptsize O(n)$<\/p>\n

\n

Q\uff1a\u4e3a\u4ec0\u4e48\u4e0d\u662f\u6807\u51c6\u5355\u8c03\u6808\u6bd4\u6808\u9876\u66f4\u5927\u5165\u6808\uff0c\u800c\u662f\u5927\u4e8e\u5df2\u77e5max\u5165\u6808\u5462\uff1f<\/p>\n

A\uff1a\u6bd4\u6808\u9876\u66f4\u5927\u5165\u6808\u5f53\u7136\u80fd\u4fdd\u8bc1\u6808\u7684\u5355\u589e\u6027\uff0c\u5173\u952e\u662f\u9000\u6808\u64cd\u4f5c\u540e\uff0c\u53ef\u80fd\u4f1a\u5b58\u5728 \u6808\u9876\uff1c\u5f53\u524d\uff1c\u66fe\u7ecf\u7684\u5de6\u4fa7\u6700\u5927<\/strong> \u60c5\u51b5\uff0c\u5982\u4f8b $\\scriptsize [1,4,2,3,5]$\uff0c\u8bfb\u5230\u6570 $\\scriptsize 2$ \u65f6 $\\scriptsize 4$ \u51fa\u6808\uff0c\u8bfb\u5230\u6570 $\\scriptsize 3$ \u65f6\u6808\u9876\u5143\u7d20\u4e3a $\\scriptsize 1$\uff0c\u5ffd\u7565\u4e86\u4e4b\u524d\u7684\u66f4\u5927\u6570 $\\scriptsize 4$<\/p>\n

Q\uff1a\u683c\u5f0f\u9519\u8bef\u4ec0\u4e48\u9b3c\uff1f<\/p>\n

A\uff1a\u60ca\u4e86\uff01\u6570\u76ee\u4e3a0\u7684\u65f6\u5019\uff0c\u6ca1\u6709\u5143\u7d20\uff0c\u66ff\u4ee3\u8f93\u51fa\u4e00\u4e2a’\\n’\uff0c\u9898\u4e2d\u786e\u5b9e\u6ca1\u8bf4\u660e\uff0c\u59e5\u59e5\u662f\u60f3\u8ba9\u6211\u4eec\u63e3\u6469\u5979\u5fc3\u601d\u561b\uff1f<\/p>\n

\n
#include <iostream>\n#include <vector>\nusing namespace std;\n\nint main() {\n    int N, t, preMax = 0;\n    vector<int> v;\n    scanf(\"%d\", &N);\n    while (N--) {\n        scanf(\"%d\", &t);\n        if (t > preMax) {\n            v.push_back(t);\n            preMax = t;\n        }\n        else while (!v.empty() && v.back() > t)\n            v.pop_back();\n    }\n\n    printf(\"%d\\n\", v.size());\n    for (int i = 0; i < v.size(); i++)\n        if (i == v.size() - 1) printf(\"%d\", v[i]);\n        else printf(\"%d \", v[i]);\n    putchar('\\n');\n    return 0;\n}\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"
\u6808 \u5355\u8c03\u6808 PAT-A1101 \u627e\u67a2\u8f74 \u2460 \u66b4\u529b\u89e3\u6cd5\uff1a\u5206\u522b\u5411\u5de6\u53f3\u67e5\u8be2\u5927\u5c0f\u7684\u66b4\u529b\u5339\u914d $\\scriptsize  … <\/p>\n
\u7ee7\u7eed\u9605\u8bfb\u201c\u6808\u53ca\u53d8\u79cd – \u559c\u65b0\u538c\u65e7\u7684\u6e23\u7537\u201d<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[12],"tags":[],"jetpack_featured_media_url":"","_links":{"self":[{"href":"http:\/\/139.196.114.170\/index.php?rest_route=\/wp\/v2\/posts\/428"}],"collection":[{"href":"http:\/\/139.196.114.170\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/139.196.114.170\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/139.196.114.170\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/139.196.114.170\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=428"}],"version-history":[{"count":11,"href":"http:\/\/139.196.114.170\/index.php?rest_route=\/wp\/v2\/posts\/428\/revisions"}],"predecessor-version":[{"id":2083,"href":"http:\/\/139.196.114.170\/index.php?rest_route=\/wp\/v2\/posts\/428\/revisions\/2083"}],"wp:attachment":[{"href":"http:\/\/139.196.114.170\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=428"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/139.196.114.170\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=428"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/139.196.114.170\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=428"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}