{"id":295,"date":"2019-09-27T11:23:21","date_gmt":"2019-09-27T03:23:21","guid":{"rendered":"http:\/\/www.guanhaobo.cn\/?p=295"},"modified":"2019-09-27T11:23:21","modified_gmt":"2019-09-27T03:23:21","slug":"%e6%b4%9b%e8%b0%b7p1513-%e7%bb%95%e9%92%89%e5%ad%90%e7%9a%84%e9%95%bf%e7%bb%b3%e5%ad%90","status":"publish","type":"post","link":"https:\/\/www.guanhaobo.cn\/?p=295","title":{"rendered":"\u6d1b\u8c37P1513 \u2014 \u7ed5\u9489\u5b50\u7684\u957f\u7ef3\u5b50"},"content":{"rendered":"<h3>\u9898\u76ee\u80cc\u666f<\/h3>\n<p>\u5e73\u9762\u4e0a\u6709N\u4e2a\u5706\u67f1\u5f62\u7684\u5927\u9489\u5b50\uff0c\u534a\u5f84\u90fd\u4e3aR,\u6240\u6709\u9489\u5b50\u7ec4\u6210\u4e00\u4e2a\u51f8\u591a\u8fb9\u5f62\u3002<\/p>\n<p>\u73b0\u5728\u4f60\u8981\u7528\u4e00\u6761\u7ef3\u5b50\u628a\u8fd9\u4e9b\u9489\u5b50\u56f4\u8d77\u6765\uff0c\u7ef3\u5b50\u76f4\u5f84\u5ffd\u7565\u4e0d\u8ba1\u3002<\/p>\n<h3>\u9898\u76ee\u63cf\u8ff0<\/h3>\n<p>\u6c42\u51fa\u7ef3\u5b50\u7684\u957f\u5ea6<\/p>\n<h3>\u9898\u76ee\u94fe\u63a5<\/h3>\n<p><a href=\"https:\/\/www.luogu.org\/problem\/P1513\" title=\"https:\/\/www.luogu.org\/problem\/P1513\">https:\/\/www.luogu.org\/problem\/P1513<\/a><\/p>\n<h3>\u8f93\u5165\u683c\u5f0f<\/h3>\n<p>\u7b2c1\u884c\u4e24\u4e2a\u6570\uff1a\u6574\u6570N(1&lt;=N&lt;=100)\u548c\u5b9e\u6570R\u3002<br \/>\n\u63a5\u4e0b\u6765N\u884c\u6309\u9006\u65f6\u9488\u987a\u5e8f\u7ed9\u51faN\u4e2a\u9489\u5b50\u4e2d\u5fc3\u7684\u5750\u6807<br \/>\n\u5750\u6807\u7684\u7edd\u5bf9\u503c\u4e0d\u8d85\u8fc7100\u3002<\/p>\n<h3>\u8f93\u51fa\u683c\u5f0f<\/h3>\n<p>\u4e00\u4e2a\u6570\uff0c\u7ef3\u5b50\u7684\u957f\u5ea6\uff0c\u7cbe\u786e\u5230\u5c0f\u6570\u70b9\u540e2\u4f4d\u3002<\/p>\n<h3>\u6837\u4f8b\u8f93\u5165<\/h3>\n<pre><code class=\"language-cpp line-numbers\">4 1\n0.0 0.0\n2.0 0.0\n2.0 2.0\n0.0 2.0\n<\/code><\/pre>\n<h3>\u6837\u4f8b\u8f93\u51fa<\/h3>\n<p><code>14.28<\/code><\/p>\n<h3>\u8bf4\u660e\/\u63d0\u793a<\/h3>\n<p>\u5982\u679c\u4f60\u7528\u6bd4\u8f83\u590d\u6742\u7684\u65b9\u6cd5AC\u4e86\uff0c\u8bf7\u60f3\u4e00\u60f3\u6709\u6ca1\u6709\u66f4\u52a0\u7b80\u4fbf\u7684\u65b9\u6cd5\u3002<br \/>\n\u672c\u9898\u6765\u81eaURAL1020\uff0c\u7ffb\u8bd1\u6765\u81eaNOCOW\u3002<\/p>\n<h3>\u9898\u76ee\u5206\u6790<\/h3>\n<p>\u7ef3\u5b50\u7ed5\u4e86\u4e00\u5708\uff0c\u7ef3\u5b50\u7684\u957f\u5ea6\u4e3a\u534a\u5f84\u4e3a R \u7684\u5706\u7684\u5468\u957f\u518d\u52a0\u4e0a\u76f8\u90bb\u9489\u5b50\u7684\u4e2d\u5fc3\u4e4b\u95f4\u7684\u8ddd\u79bb\u3002\u5982\u679c\u8fd8\u4e0d\u592a\u6e05\u695a\uff0c\u53ef\u4ee5\u628a\u6837\u4f8b\u4e2d\u7684\u56fe\u5f62\u753b\u51fa\u6765\u3002<\/p>\n<h3>AC\u4ee3\u7801<\/h3>\n<pre><code class=\"language-cpp line-numbers\">#include &lt;bits\/stdc++.h&gt;\nusing namespace std;\n\n\/\/\u4e00\u4e2a r \u5706\u7684\u5468\u957f\u52a0\u6240\u6709\u9489\u5b50\u4e2d\u5fc3\u7684\u8ddd\u79bb\nint main()\n{\n    int n;\n    double x[100], y[100], ans = 0, r; \/\/\u6ce8\u610fr\u662f\u5b9e\u6570\n    cin &gt;&gt; n &gt;&gt; r;\n    ans = 2 * M_PI * r;\n    for (int i = 0; i &lt; n; i++)\n    {\n        cin &gt;&gt; x[i] &gt;&gt; y[i];\n        if (i &gt; 0)\n            ans += sqrt(pow(x[i] - x[i - 1], 2) + pow(y[i] - y[i - 1], 2));\n    }\n    ans += sqrt(pow(x[n - 1] - x[0], 2) + pow(y[n - 1] - y[0], 2));\n    printf(\"%.2f\\n\", ans);\n    return 0;\n}\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>\u9898\u76ee\u80cc\u666f \u5e73\u9762\u4e0a\u6709N\u4e2a\u5706\u67f1\u5f62\u7684\u5927\u9489\u5b50\uff0c\u534a\u5f84\u90fd\u4e3aR,\u6240\u6709\u9489\u5b50\u7ec4\u6210\u4e00\u4e2a\u51f8\u591a\u8fb9\u5f62\u3002 \u73b0\u5728\u4f60\u8981\u7528\u4e00\u6761\u7ef3\u5b50\u628a\u8fd9\u4e9b\u9489\u5b50\u56f4\u8d77 [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[54,56],"class_list":["post-295","post","type-post","status-publish","format-standard","hentry","category-algo","tag-54","tag-56"],"_links":{"self":[{"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/posts\/295","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=295"}],"version-history":[{"count":0,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/posts\/295\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=295"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=295"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=295"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}