{"id":787,"date":"2024-11-30T18:27:49","date_gmt":"2024-11-30T10:27:49","guid":{"rendered":"http:\/\/8.138.167.183\/?p=787"},"modified":"2024-11-30T18:27:49","modified_gmt":"2024-11-30T10:27:49","slug":"graham%e6%89%ab%e6%8f%8f%e6%b3%95%e8%a7%a3%e5%86%b3%e5%87%b8%e5%8c%85%e8%be%b9%e7%95%8c%e9%97%ae%e9%a2%98","status":"publish","type":"post","link":"https:\/\/heqiwei.cn\/index.php\/2024\/11\/30\/graham%e6%89%ab%e6%8f%8f%e6%b3%95%e8%a7%a3%e5%86%b3%e5%87%b8%e5%8c%85%e8%be%b9%e7%95%8c%e9%97%ae%e9%a2%98\/","title":{"rendered":"Graham\u626b\u63cf\u6cd5\u89e3\u51b3\u51f8\u5305\u8fb9\u754c\u95ee\u9898"},"content":{"rendered":"\n<p>\u5728\u4e00\u4e2a\u9633\u5149\u660e\u5a9a\u7684\u4e0b\u5348\uff0c Mr.Box\u4e0e<strong> hdu2202 \u6700\u5927\u4e09\u89d2\u5f62<\/strong> \u76f8\u9047\u4e86\uff0c\u7ecf\u8fc7\u4e00\u756a\u5b66\u4e60\u548c\u601d\u8003\uff0c\u4ed6\u6700\u7ec8AC\u4e86\u8fd9\u9053\u9898\uff0c\u9898\u9762\u5982\u4e0b\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/heqiwei.cn\/wp-content\/uploads\/2024\/11\/image-273-1024x726.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"726\" data-original=\"http:\/\/heqiwei.cn\/wp-content\/uploads\/2024\/11\/image-273-1024x726.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-789\"  sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/div><\/figure>\n\n\n\n<p>\u601d\u8def\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u5229\u7528graham\u7b97\u6cd5\u7b97\u51fa\u6240\u7ed9\u70b9\u96c6\u4e2d\u76f8\u8fde\u8d77\u6765\u53ef\u4ee5\u5305\u56f4\u4f4f\u6240\u6709\u70b9\u7684\u5b50\u96c6P\uff0c\u5982\u4e0b\u56fe\uff1a<\/li>\n<\/ol>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/heqiwei.cn\/wp-content\/uploads\/2024\/11\/image-274.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"318\" height=\"236\" data-original=\"http:\/\/heqiwei.cn\/wp-content\/uploads\/2024\/11\/image-274.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-790\"  sizes=\"auto, (max-width: 318px) 100vw, 318px\" \/><\/div><\/figure>\n\n\n\n<p>2. \u66b4\u529b\u679a\u4e3e\u5b50\u96c6P\u4e2d\u4efb\u610f\u4e09\u4e2a\u70b9\u5bf9\uff0c\u66f4\u65b0\u6700\u5927\u4e09\u89d2\u5f62\u9762\u79ef\u3002<\/p>\n\n\n\n<p><\/p>\n\n\n\n<p>\u4e0d\u96be\u770b\u51fa\uff0c\u672c\u9898\u7684\u5173\u952e\u5728\u4e8e\u6c42\u51fa\u5b50\u96c6P\uff0c\u4e0b\u9762\u4ecb\u7ecdGraham\u626b\u63cf\u6cd5\uff1a<\/p>\n\n\n\n<p>1. \u627e\u51fa\u8f93\u5165\u7684\u70b9\u5750\u6807\u4e2d\uff0c\u4f18\u5148\u6700\u9760\u4e0b\uff0c\u6b21\u4f18\u6700\u9760\u5de6\u7684\u70b9\uff1b<\/p>\n\n\n\n<p>2. \u4ee5\u8be5\u70b9\u4e3a\u539f\u70b9\u5e73\u79fb\u5750\u6807\u7cfb\uff1b<\/p>\n\n\n\n<p>3. \u5229\u7528\u5185\u7f6e\u7684<mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-contrast-3-color\">atan2\u51fd\u6570<\/mark>\u5199cmp\u51fd\u6570\uff0c\u5c06\u70b9\u96c6\u6309\u7167\u4f18\u5148\u4e0ex\u8f74\u5939\u89d2\u6700\u5c0f\uff0c\u6b21\u4f18\u4e0e\u539f\u70b9\u6700\u8fd1\u7684\u539f\u5219\u6392\u5e8f\uff1b<\/p>\n\n\n\n<p class=\"has-text-align-left\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-contrast-3-color\">atan2\u51fd\u6570\uff1a<strong>atan2(y, x)<\/strong>\uff0cC++\u4e2d\u4e00\u79cddouble\u7c7b\u578b\u7684\u53cd\u6b63\u5207\u51fd\u6570\uff0c\u8fd4\u56de\u503c\u4e3a\u5f27\u5ea6\uff0c\u662f\u70b9(0\uff0c0)\u548c(x\uff0cy)\u7684<strong>\u8fde\u7ebf\u4e0eX\u8f74\u6b63\u534a\u8f74\u7684\u5939\u89d2<\/strong>\uff0c\u5176\u503c\u57df\u4e3a\u00a0<strong>[-\u03c0\uff0c\u03c0]<\/strong>\u00a0\uff08\u5f53y=0\u65f6\uff0c\u53ef\u4ee5\u53d6\u5230\u00b1\u03c0\uff09\uff0c\u4e14\u5728\u7b2c\u4e00\u4e8c\u8c61\u9650\u4e3a\u6b63\uff0c\u5728\u7b2c\u4e09\u56db\u8c61\u9650\u4e3a\u8d1f\uff0c\u65e0\u7279\u6b8a\u5934\u6587\u4ef6<\/mark><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>bool cmp(point a, point b)\n{\n    if (atan2(a.y, a.x) != atan2(b.y, b.x))\n        return atan2(a.y, a.x) &lt; atan2(b.y, b.x);\n    else return a.x &lt; a.y;\n} \n\/* \u5148\u5224\u65ad\u4e24\u70b9\u4e0ex\u8f74\u8fde\u7ebf\u7684\u7684\u89d2\u5ea6\u8c01\u66f4\u5c0f\uff0c\u76f8\u540c\u5219\u8fd4\u56de\u79bb\u539f\u70b9\u66f4\u8fd1\u7684\u90a3\u4e2a *\/<\/code><\/pre>\n\n\n\n<p>4. \u5c06\u70b9\u96c6\u4e2d\u524d\u4e24\u4e2a\u5143\u7d20\u5206\u522b\u5165\u6808\uff1b<\/p>\n\n\n\n<p>5. \u904d\u5386\u63a5\u4e0b\u6765\u70b9\u96c6\u4e2d\u6bcf\u4e2a\u70b9\uff0c\u8bbe\u4e3at\uff0c\u8bbe\u6808\u9876\u5143\u7d20\u4e3ap1\uff0c\u6808\u9876\u4e0b\u9762\u4e00\u4e2a\u5143\u7d20\u4e3ap0\u3002\u5219\u5982\u679c\u5411\u91cf p0p1 x p1p2 &lt; 0\uff0c\u5219\u5c06\u6808\u9876\u5143\u7d20\u51fa\u6808\uff0c\u4e00\u76f4\u5faa\u73af\u81f3\u53c9\u79ef\u7ed3\u679c\u4e3a\u6b63\uff0c\u518d\u5c06t\u5165\u6808\uff1b<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>bool cross_mul(point a, point b, point c) \n{\n    int x1 = b.x - a.x, y1 = b.y - a.y;\n    int x2 = c.x - a.x, y2 = c.y - a.y;\n    return x1 * y2 - x2 * y1 > 0;\n} \/\/ \u8fd4\u56de\u5411\u91cfab\u53c9\u4e58bc\u662f\u5426\u4e3a\u6b63\n\n\/* graham\u6838\u5fc3\u4ee3\u7801\uff0cn\u4e3a\u8f93\u5165\u70b9\u96c6\u5bb9\u91cf\uff0ccnt\u4e3a\u6808\u5185\u5143\u7d20\u4e2a\u6570\uff0c\u521d\u59cb\u503c\u4e3a0 *\/\nfor (int i = 2; i &lt; n; ++i) \n{\n    while (i >= 0 &amp;&amp; !cross_mul(stack&#91;cnt - 2], stack&#91;cnt - 1], p&#91;i]))\n        cnt--;\n    stack&#91;cnt++] = p&#91;i];\n}<\/code><\/pre>\n\n\n\n<p>6. \u6700\u540e\u6808\u5185\u7684\u5c31\u90fd\u662f\u51f8\u5305\u7684\u8fb9\u754c\u70b9\u3002<\/p>\n\n\n\n<p><\/p>\n\n\n\n<p>\u8ffd\u52a0\u4e00\u4e2a\u5229\u7528\u53c9\u4e58\u5feb\u901f\u8ba1\u7b97\u4e09\u89d2\u5f62\u9762\u79ef\u7684\u516c\u5f0f<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>S=|(x1*y2+x2*y3+x3*y1-y1*x2-y2*x3-y3*x1)\/2|<\/code><\/pre>\n\n\n\n<p>OVER<\/p>\n\n\n\n<p>\u6700\u540e\u8bb0\u5f55\u4e00\u4e0b\u6700\u8fd1\u542c\u7684\u300a\u5f53\u7231\u5df2\u6210\u5f80\u4e8b\u300b\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\u201c\u4e0d\u8981\u95ee\u6211\u662f\u5426\u518d\u76f8\u9022\uff0c\n\u4e0d\u8981\u7ba1\u6211\u662f\u5426\u8a00\u4e0d\u7531\u8877\u3002\u201d<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>\u5728\u4e00\u4e2a\u9633\u5149\u660e\u5a9a\u7684\u4e0b\u5348\uff0c Mr.Box\u4e0e hdu2202 \u6700\u5927\u4e09\u89d2\u5f62 \u76f8\u9047\u4e86\uff0c\u7ecf\u8fc7\u4e00\u756a\u5b66\u4e60\u548c\u601d\u8003\uff0c\u4ed6\u6700\u7ec8AC\u4e86\u8fd9 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-787","post","type-post","status-publish","format-standard","hentry","category-1"],"_links":{"self":[{"href":"https:\/\/heqiwei.cn\/index.php\/wp-json\/wp\/v2\/posts\/787","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/heqiwei.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/heqiwei.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/heqiwei.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/heqiwei.cn\/index.php\/wp-json\/wp\/v2\/comments?post=787"}],"version-history":[{"count":0,"href":"https:\/\/heqiwei.cn\/index.php\/wp-json\/wp\/v2\/posts\/787\/revisions"}],"wp:attachment":[{"href":"https:\/\/heqiwei.cn\/index.php\/wp-json\/wp\/v2\/media?parent=787"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/heqiwei.cn\/index.php\/wp-json\/wp\/v2\/categories?post=787"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/heqiwei.cn\/index.php\/wp-json\/wp\/v2\/tags?post=787"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}