{"id":145,"date":"2018-11-11T20:42:41","date_gmt":"2018-11-11T12:42:41","guid":{"rendered":"https:\/\/blog.indeex.club\/?p=145"},"modified":"2020-06-20T23:12:31","modified_gmt":"2020-06-20T15:12:31","slug":"%e5%9b%be%e5%bd%a2%e6%bc%94%e7%ae%97-%e5%af%bb%e8%b7%af%e7%ae%97%e6%b3%95","status":"publish","type":"post","link":"https:\/\/blog.indeex.club\/index.php\/2018\/11\/11\/%e5%9b%be%e5%bd%a2%e6%bc%94%e7%ae%97-%e5%af%bb%e8%b7%af%e7%ae%97%e6%b3%95\/","title":{"rendered":"\u56fe\u5f62\u6f14\u7b97&#8211;\u5bfb\u8def\u7b97\u6cd5"},"content":{"rendered":"<hr \/>\n<h3>\u524d\u8a00<\/h3>\n<p>\u5bfb\u8def\u7b97\u6cd5\u5927\u81f4\u53ef\u4ee5\u5206\u4e3a\u300c\u6df1\u5ea6\u4f18\u5148\u641c\u7d22\uff08Depth-First Search\uff0cDFS\uff09\u3001\u5e7f\u5ea6\u4f18\u5148\u641c\u7d22\uff08Breath-First Search\uff0cBFS\uff09\u548c\u6700\u4f73\u4f18\u5148\u641c\u7d22\uff08Best-First Search\uff0cBestFS\uff09\u4e09\u5927\u7c7b\u3002<\/p>\n<p>\u5bf9\u4e8e\u6700\u4f73\u4f18\u5148\u641c\u7d22\u90e8\u4efd\uff0c\u8f83\u4e3a\u719f\u6089\u7684\u662fA*\u5bfb\u8def\u7b97\u6cd5\u3002<\/p>\n<h3>\u56fe\u5f62\u63cf\u8ff0<\/h3>\n<p>\u56fe\u5f62\u662f\u7531\u8282\u70b9\uff08node\uff09\u4e0e\u7ebf\uff08edge\uff09\u7ec4\u6210\u7684\u3002\u6bd4\u5982\uff0c\u4e0b\u9762\u5305\u542b\u516d\u4e2a\u8282\u70b9\u4e0e\u5341\u6761\u7ebf\u7ec4\u6210\u7684\u7b80\u5355\u56fe\u5f62\uff1a<\/p>\n<p><img src=\"https:\/\/hungking.cc\/assets\/imgs\/indeex.cc\/astar1.jpg\" alt=\"A Star\" \/><\/p>\n<h3>\u6df1\u5ea6\u4f18\u5148\u641c\u7d22<\/h3>\n<blockquote><p>\n  \u6df1\u5ea6\u4f18\u5148\u641c\u7d22\uff08DFS\uff09\uff0c\u5c31\u662f\u4e00\u76f4\u641c\u7d22\u8ddd\u5f53\u524d\u8282\u70b9\u6700\u8fd1\u7684\u6ca1\u6709\u88ab\u8bbf\u95ee\u8fc7\u7684\u6700\u8fd1\u4e34\u8282\u70b9\u7684\u4e00\u79cd\u65b9\u6cd5\n<\/p><\/blockquote>\n<p>\u8fd9\u79cd\u65b9\u6cd5\u53ef\u4ee5\u91c7\u7528\u300c<strong>\u9012\u5f52\u641c\u7d22<\/strong>\u300d\u5b8c\u6210\uff1a<\/p>\n<pre><code class=\"language-js line-numbers\">dfs(g, node) {\n  if (g[node].v !=0) return;   \/\/ \u5982\u679c\u5df2\u8bbf\u95ee\u8fc7\uff0c\u4e0d\u518d\u8bbf\u95ee\n  trace(\"%d=&gt;\", node);        \/\/ \u6253\u5370\u51fa\u6ca1\u6709\u88ab\u8bbf\u95ee\u8fc7\u7684\u8282\u70b9\n  g[node].v = 1;              \/\/   \u8bbe\u4e3a\u5df2\u8bbf\u95ee\n  let neighbors = g[node].n;  \/\/ \u53d6\u51fa\u76f8\u90bb\u8282\u70b9\n  for (let i in neighbors) {  \/\/ \u8bbf\u95ee\u6bcf\u4e2a\u4e34\u754c\u70b9\n    dfs(g, neighbors[i]);     \/\/   \u7ee7\u7eed\u8bbf\u95ee\u5176\u4ed6\u4e34\u8282\u70b9\n  }\n}\n<\/code><\/pre>\n<p>\u7ed3\u679c\u5982\u4e0b\uff1a<\/p>\n<p><img src=\"https:\/\/hungking.cc\/assets\/imgs\/indeex.cc\/astar2.jpg\" alt=\"A Star\" \/><\/p>\n<h3>\u5e7f\u5ea6\u4f18\u5148\u641c\u7d22<\/h3>\n<p>\u867d\u7136\u6df1\u5ea6\u4f18\u5148\u641c\u7d22\u53ef\u4ee5\u641c\u7d22\u6574\u4e2a\u56fe\u5f62\uff0c\u4f46\u662f\u5f88\u53ef\u80fd\u7ed5\u4e86\u5f88\u4e45\u624d\u627e\u5230\u76ee\u6807\uff08\u6bd4\u5982\u8def\u5f84\u592a\u957f\uff09\uff0c\u4f1a\u6d88\u8017\u5f88\u957f\u65f6\u95f4\u3002\u800c\u300c\u5e7f\u5ea6\u4f18\u5148\u641c\u7d22\u300d\uff08BFS\uff09\u5c31\u53ef\u4ee5<strong>\u89e3\u51b3\u8017\u65f6\u95ee\u9898<\/strong>\u3002<\/p>\n<blockquote><p>\n  \u5e7f\u5ea6\u4f18\u5148\u641c\u7d22\u662f\u4ece\u4e00\u4e2a\u8282\u70b9\u5f00\u59cb\uff0c\u641c\u7d22\u6bcf\u4e2a\u76f8\u90bb\u8282\u70b9\u548c\u76f8\u90bb\u8282\u70b9\u4e0b\u9762\u7684\u76f8\u90bb\u8282\u70b9\uff0c\u4f18\u5148\u8bbf\u95ee\u6df1\u5ea6\u6700\u6d45\u7684\u8282\u70b9\u3002\n<\/p><\/blockquote>\n<p><img src=\"https:\/\/hungking.cc\/assets\/imgs\/indeex.cc\/astar3.jpg\" alt=\"A Star\" \/><\/p>\n<p>\u5e7f\u5ea6\u4f18\u5148\u641c\u7d22\uff0c\u91c7\u7528\u300c<strong>\u5148\u8fdb\u5148\u51fa<\/strong>\u300d\uff08First-in First-Out\uff0cFIFO\uff09\u7684\u65b9\u5f0f\u6765\u7ba1\u7406\u6240\u6709\u8282\u70b9\uff0c\u56e0\u6b64\u901a\u5e38\u5728\u300c\u5e7f\u5ea6\u4f18\u5148\u641c\u7d22\u300d\u91cc\u4f1a\u6709\u4e2a\u961f\u5217\uff08queue\uff09\u7ed3\u6784\uff0c\u4ee5\u4e0b\u662f\u5e7f\u5ea6\u4f18\u5148\u641c\u7d22\u7684\u7b97\u6cd5\uff1a<\/p>\n<pre><code class=\"language-js line-numbers\">dequeue(a) {\n  return a.shift();\n}\nbfs(g, q) {\n  if (q.length == 0) return;\n  var node = dequeue(q);\n  if (g[node].v == 0)\n    g[node].v = 1;\n  else\n    return;\n  trace(\"%d=&gt;\", node);\n  var neighbors = g[node].n; \/\/\u53d6\u51fa\u76f8\u90bb\u8282\u70b9\u3002\n  for (var i in neighbors) {\n    var n = neighbors[i];\n    if (!g[n].visited)\n      q.push(n);             \/\/\u5c06\u6ca1\u6709\u8bbf\u95ee\u8fc7\u7684\u76f8\u90bb\u8282\u70b9\u653e\u5165\u961f\u5217\n  }\n  bfs(g, q);\n}\n<\/code><\/pre>\n<h3>\u6700\u4f73\u4f18\u5148\u641c\u7d22<\/h3>\n<p>\u4f46\u662f\uff0c\u6df1\u5ea6\u641c\u5bfb\u4e00\u76f4\u5728\u6ca1\u6709\u76ee\u6807\u7684\u641c\u7d22\uff0c\u800c\u5e7f\u5ea6\u641c\u5bfb\u4f1a\u6d88\u8017\u592a\u591a\u5167\u5b58\uff0c\u6548\u7387\u8f83\u4f4e\uff0c\u65e0\u6cd5\u5f88\u5feb\u7684\u627e\u5230\u76ee\u6807\u70b9\u3002<\/p>\n<p>\u5982\u679c<strong>\u77e5\u9053\u54ea\u4e9b\u70b9\u8ddd\u79bb\u76ee\u6807\u70b9\u6700\u8fd1<\/strong>\u7684\u8bdd\uff0c\u90a3\u5c31\u80fd\u91c7\u7528\u300c\u6700\u4f73\u4f18\u5148\u641c\u7d22\uff08Best-First Search\uff09\u3002<\/p>\n<p>\u6700\u4f73\u4f18\u5148\u641c\u7d22\u65b9\u6cd5\u4e0e\u5e7f\u5ea6\u4f18\u5148\u641c\u5bfb\u7c7b\u4f3c\uff0c\u4f46\u662f\u5e76\u4e0d\u4f7f\u7528\u7528\u961f\u5217\uff08queue\uff09\uff0c\u800c\u662f\u91c7\u7528\u4e00\u79cd\u6839\u636e\u4f18\u5148\u7a0b\u5ea6\u6392\u5e8f\u7684\u7ed3\u6784\uff0c\u6bcf\u6b21\u90fd\u53d6\u51fa\u6700\u597d\u7684\u90a3\u4e2a\u8282\u70b9\u7ee7\u7eed\u641c\u7d22\u3002<\/p>\n<p>\u4f46\u662f\uff0c\u4e00\u822c\u8282\u70b9\u7684\u597d\u574f\u5f88\u96be\u77e5\u9053\uff0c\u5355\u7eaf\u91c7\u7528\u8ddd\u79bb\u6700\u8fd1\u5f80\u5f80\u4f1a\u8fc7\u5ea6\u7b80\u5316\u95ee\u9898\uff0c\u8fd9\u4e5f\u662f\u662f\u6700\u4f73\u4f18\u5148\u641c\u7d22\u6bd4\u8f83\u9ebb\u70e6\u7684\u5730\u65b9\u3002<\/p>\n<p>\u901a\u5e38\u60c5\u51b5\uff0c\u53ea\u8981\u7b26\u5408$h(x) \\leq d(x,y) + h(y)$\uff0c\u5c31\u4e0d\u7528\u8003\u8651\u592a\u591a\uff0c\u5e38\u7528<strong>A*\u7b97\u6cd5<\/strong>\u6765\u8fdb\u884c\u5feb\u901f\u641c\u7d22\uff0c\u8fd9\u79cd\u65b9\u6cd5\u6bd4\u5e7f\u5ea6\u4f18\u5148\u641c\u7d22\u5feb\u5f88\u591a\uff0c\u56e0\u4e3aA*\u7b97\u6cd5\u4e0d\u4f1a\u641c\u7d22\u6240\u6709\u8282\u70b9\uff0c\u800c\u662f\u6709\u7cfb\u7edf\u7684\u671d\u7740\u6574\u4f53\u8f83\u597d\u7684\u65b9\u5411\u641c\u7d22\uff0c\u8fd9\u79cd\u65b9\u6cd5\u5728\u6e38\u620f\u9886\u57df\u91cc\u5e38\u88ab\u7528\u5728NPC\uff08\u975e\u73a9\u5bb6\u89d2\u8272\uff09\u5bfb\u627e\u4e0a\uff0c\u662f\u5bfb\u8def\u7b97\u6cd5\u4e2d\u8f83\u5f3a\u5927\u7b97\u6cd5\u4e4b\u4e00\u3002\u8fd9\u91cc\u4e0d\u518d\u8d58\u8ff0\u3002<\/p>\n<p>code enjoy! &#x1f92a;&#x1f92a;&#x1f92a;<\/p>\n<p>\u4f5c\u8005\uff1aindeex<\/p>\n<p>\u94fe\u63a5\uff1a<a class=\"wp-editor-md-post-content-link\" href=\"https:\/\/indeex.cc\/\">https:\/\/indeex.cc<\/a><\/p>\n<p>\u8457\u4f5c\u6743\u5f52\u4f5c\u8005\u6240\u6709\u3002\u5546\u4e1a\u8f6c\u8f7d\u8bf7\u8054\u7cfb\u4f5c\u8005\u83b7\u5f97\u6388\u6743\uff0c\u975e\u5546\u4e1a\u8f6c\u8f7d\u8bf7\u6ce8\u660e\u51fa\u5904\u3002<\/p>\n<hr \/>\n","protected":false},"excerpt":{"rendered":"<p>\u524d\u8a00 \u5bfb\u8def\u7b97\u6cd5\u5927\u81f4\u53ef\u4ee5\u5206\u4e3a\u300c\u6df1\u5ea6\u4f18\u5148\u641c\u7d22\uff08Depth-First Search\uff0cDFS\uff09\u3001\u5e7f\u5ea6\u4f18\u5148\u641c<a href=\"https:\/\/blog.indeex.club\/index.php\/2018\/11\/11\/%e5%9b%be%e5%bd%a2%e6%bc%94%e7%ae%97-%e5%af%bb%e8%b7%af%e7%ae%97%e6%b3%95\/\" class=\"read-more\">Read More<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[3],"tags":[4],"_links":{"self":[{"href":"https:\/\/blog.indeex.club\/index.php\/wp-json\/wp\/v2\/posts\/145"}],"collection":[{"href":"https:\/\/blog.indeex.club\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.indeex.club\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.indeex.club\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.indeex.club\/index.php\/wp-json\/wp\/v2\/comments?post=145"}],"version-history":[{"count":1,"href":"https:\/\/blog.indeex.club\/index.php\/wp-json\/wp\/v2\/posts\/145\/revisions"}],"predecessor-version":[{"id":150,"href":"https:\/\/blog.indeex.club\/index.php\/wp-json\/wp\/v2\/posts\/145\/revisions\/150"}],"wp:attachment":[{"href":"https:\/\/blog.indeex.club\/index.php\/wp-json\/wp\/v2\/media?parent=145"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.indeex.club\/index.php\/wp-json\/wp\/v2\/categories?post=145"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.indeex.club\/index.php\/wp-json\/wp\/v2\/tags?post=145"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}