{"id":446,"date":"2025-10-22T19:17:56","date_gmt":"2025-10-22T11:17:56","guid":{"rendered":"https:\/\/heyingnian.com\/?p=446"},"modified":"2025-10-22T19:18:17","modified_gmt":"2025-10-22T11:18:17","slug":"leetcode-114","status":"publish","type":"post","link":"https:\/\/heyingnian.com\/index.php\/2025\/10\/22\/leetcode-114\/","title":{"rendered":"\u4e8c\u53c9\u6811\u5c55\u5f00\u4e3a\u94fe\u8868"},"content":{"rendered":"\n<h1 class=\"wp-block-heading\">\ud83d\udd17 \u4e8c\u53c9\u6811\u5c55\u5f00\u4e3a\u94fe\u8868<\/h1>\n\n\n\n<p><strong>\u9898\u76ee\u6765\u6e90<\/strong>\uff1a<a target=\"_blank\" rel=\"noreferrer noopener\"><a href=\"https:\/\/leetcode.cn\/problems\/flatten-binary-tree-to-linked-list\/description\/?envType=study-plan-v2&amp;envId=top-100-liked\" target=\"_blank\" rel=\"noopener\">114. \u4e8c\u53c9\u6811\u5c55\u5f00\u4e3a\u94fe\u8868 &#8211; \u529b\u6263\uff08LeetCode\uff09<\/a><\/a><\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\ud83d\udccc \u9898\u76ee\u63cf\u8ff0<\/h2>\n\n\n\n<p>\u7ed9\u4f60\u4e8c\u53c9\u6811\u7684\u6839\u8282\u70b9 <code>root<\/code>\uff0c\u8bf7\u4f60\u5c06\u5b83<strong>\u5c55\u5f00\u4e3a\u4e00\u4e2a\u5355\u94fe\u8868<\/strong>\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5c55\u5f00\u540e\u7684\u5355\u94fe\u8868\u5e94\u8be5\u540c\u6837\u4f7f\u7528\u00a0<code>TreeNode<\/code>\uff1b<\/li>\n\n\n\n<li>\u5176\u4e2d\u00a0<strong><code>right<\/code>\u00a0\u5b50\u6307\u9488\u6307\u5411\u94fe\u8868\u4e2d\u4e0b\u4e00\u4e2a\u8282\u70b9<\/strong>\uff0c\u800c\u00a0<strong><code>left<\/code>\u00a0\u5b50\u6307\u9488\u59cb\u7ec8\u4e3a\u00a0<code>null<\/code><\/strong>\uff1b<\/li>\n\n\n\n<li>\u5c55\u5f00\u540e\u7684\u5355\u94fe\u8868\u5e94\u8be5\u4e0e\u4e8c\u53c9\u6811\u00a0<strong>\u5148\u5e8f\u904d\u5386\u987a\u5e8f\u76f8\u540c<\/strong>\u3002<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u2705 \u793a\u4f8b\u89e3\u6790<\/h2>\n\n\n\n<p><strong>\u793a\u4f8b 1\uff1a<\/strong><\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/heyingnian.com\/wp-content\/uploads\/2025\/10\/image-10.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"1021\" height=\"461\" data-original=\"https:\/\/heyingnian.com\/wp-content\/uploads\/2025\/10\/image-10.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-447\"  sizes=\"auto, (max-width: 1021px) 100vw, 1021px\" \/><\/div><\/figure>\n\n\n\n<pre class=\"wp-block-preformatted\"><code>\u8f93\u5165\uff1aroot = [1,2,5,3,4,null,6]<br>\u8f93\u51fa\uff1a[1,null,2,null,3,null,4,null,5,null,6]<\/code><\/pre>\n\n\n\n<p>\u89e3\u91ca\uff1a<br>\u5148\u5e8f\u904d\u5386\u5e8f\u5217\u4e3a <code>[1,2,3,4,5,6]<\/code>\uff0c\u5c55\u5f00\u540e\u6bcf\u4e2a\u8282\u70b9\u53ea\u6709\u53f3\u5b69\u5b50\uff0c\u5f62\u6210\u4e00\u6761\u5411\u53f3\u5ef6\u4f38\u7684\u94fe\u3002<\/p>\n\n\n\n<p><strong>\u793a\u4f8b 2\uff1a<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-preformatted\"><code>\u8f93\u5165\uff1aroot = []<br>\u8f93\u51fa\uff1a[]<\/code><\/pre>\n\n\n\n<p><strong>\u793a\u4f8b 3\uff1a<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-preformatted\"><code>\u8f93\u5165\uff1aroot = [0]<br>\u8f93\u51fa\uff1a[0]<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u26a0\ufe0f \u63d0\u793a<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u6811\u4e2d\u8282\u70b9\u6570\u5728\u8303\u56f4\u00a0<code>[0, 2000]<\/code>\u00a0\u5185<\/li>\n\n\n\n<li><code>-100 &lt;= Node.val &lt;= 100<\/code><\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\ud83d\udca1 \u89e3\u6cd5\uff1a\u8fed\u4ee3\uff08\u539f\u5730\u4fee\u6539\uff09\u2014\u2014 O(n) \u65f6\u95f4\uff0cO(1) \u7a7a\u95f4<\/h2>\n\n\n\n<pre class=\"wp-block-code\"><code>class Solution {\n    public void flatten(TreeNode root) {\n        while (root != null) {\n            if (root.left == null) {\n                \/\/ \u65e0\u5de6\u5b50\u6811\uff0c\u76f4\u63a5\u5411\u53f3\u79fb\u52a8\n                root = root.right;\n            } else {\n                \/\/ \u627e\u5230\u5de6\u5b50\u6811\u7684\u6700\u53f3\u8282\u70b9\n                TreeNode left = root.left;\n                while (left.right != null) {\n                    left = left.right;\n                }\n                \/\/ \u5c06\u539f\u53f3\u5b50\u6811\u63a5\u5230\u5de6\u5b50\u6811\u6700\u53f3\u8282\u70b9\u7684\u53f3\u4fa7\n                left.right = root.right;\n                \/\/ \u5c06\u5de6\u5b50\u6811\u79fb\u5230\u53f3\u4fa7\n                root.right = root.left;\n                root.left = null;\n                \/\/ \u7ee7\u7eed\u5904\u7406\u4e0b\u4e00\u4e2a\u8282\u70b9\n                root = root.right;\n            }\n        }\n    }\n}<\/code><\/pre>\n\n\n\n<p>\u2705 <strong>\u5173\u952e\u70b9<\/strong>\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5bf9\u6bcf\u4e2a\u6709\u5de6\u5b50\u6811\u7684\u8282\u70b9\uff0c<strong>\u5c06\u53f3\u5b50\u6811\u201c\u6302\u201d\u5230\u5de6\u5b50\u6811\u7684\u6700\u53f3\u7aef<\/strong>\uff0c\u518d\u628a\u5de6\u5b50\u6811\u6574\u4f53\u79fb\u5230\u53f3\u8fb9\u3002<\/li>\n\n\n\n<li><strong>\u539f\u5730\u4fee\u6539<\/strong>\uff0c\u4e0d\u4f7f\u7528\u989d\u5916\u6570\u636e\u7ed3\u6784\uff0c\u7a7a\u95f4\u590d\u6742\u5ea6\u4e3a O(1)\u3002<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\ud83d\udcca \u590d\u6742\u5ea6\u5206\u6790<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u65f6\u95f4\u590d\u6742\u5ea6<\/strong>\uff1a<code>O(n)<\/code><br>\u6bcf\u4e2a\u8282\u70b9\u6700\u591a\u88ab\u8bbf\u95ee\u4e24\u6b21\uff08\u4e00\u6b21\u627e\u6700\u53f3\uff0c\u4e00\u6b21\u4e3b\u5faa\u73af\uff09\uff0c\u603b\u4f53\u4ecd\u662f\u7ebf\u6027\u65f6\u95f4\u3002<\/li>\n\n\n\n<li><strong>\u7a7a\u95f4\u590d\u6742\u5ea6<\/strong>\uff1a<code>O(1)<\/code><br>\u4ec5\u4f7f\u7528\u5e38\u6570\u4e2a\u6307\u9488\u53d8\u91cf\uff0c<strong>\u65e0\u9700\u9012\u5f52\u6808\u6216\u961f\u5217<\/strong>\uff0c\u771f\u6b63\u5b9e\u73b0\u539f\u5730\u5c55\u5f00\u3002<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\ud83e\udde9 \u89e3\u9898\u601d\u8def<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">\u4e3a\u4ec0\u4e48\u80fd\u7528\u8fd9\u79cd\u201c\u526a\u5207-\u62fc\u63a5\u201d\u7b56\u7565\uff1f<\/h3>\n\n\n\n<p>\u56e0\u4e3a<strong>\u5148\u5e8f\u904d\u5386\u987a\u5e8f = \u6839 \u2192 \u5de6\u5b50\u6811\u5168\u90e8 \u2192 \u53f3\u5b50\u6811\u5168\u90e8<\/strong>\u3002<br>\u6240\u4ee5\uff0c\u5bf9\u4e8e\u5f53\u524d\u8282\u70b9\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u5de6\u5b50\u6811\u7684\u6240\u6709\u8282\u70b9<strong>\u5fc5\u987b\u6392\u5728\u53f3\u5b50\u6811\u4e4b\u524d<\/strong>\uff1b<\/li>\n\n\n\n<li>\u800c\u5de6\u5b50\u6811\u5185\u90e8\u5df2\u662f\u5148\u5e8f\u7ed3\u6784\uff0c\u53ea\u9700\u5c06\u5176\u201c\u5c3e\u90e8\u201d\u4e0e\u53f3\u5b50\u6811\u201c\u5934\u90e8\u201d\u8fde\u63a5\u5373\u53ef\u3002<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\">\u7b97\u6cd5\u6b65\u9aa4\uff1a<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u4ece\u6839\u8282\u70b9\u5f00\u59cb\uff0c\u9010\u4e2a\u5411\u53f3\u79fb\u52a8\uff08\u56e0\u4e3a\u5c55\u5f00\u540e\u53ea\u6709\u53f3\u6307\u9488\uff09\u3002<\/li>\n\n\n\n<li>\u82e5\u5f53\u524d\u8282\u70b9\u00a0<strong>\u6ca1\u6709\u5de6\u5b50\u6811<\/strong>\uff0c\u76f4\u63a5\u8fdb\u5165\u53f3\u5b50\u6811\u3002<\/li>\n\n\n\n<li>\u82e5\u6709\u5de6\u5b50\u6811\uff1a\n<ul class=\"wp-block-list\">\n<li>\u627e\u5230\u5176<strong>\u5de6\u5b50\u6811\u7684\u6700\u53f3\u8282\u70b9<\/strong>\uff08\u5373\u5148\u5e8f\u904d\u5386\u4e2d\u5de6\u5b50\u6811\u7684\u6700\u540e\u4e00\u4e2a\u8282\u70b9\uff09\uff1b<\/li>\n\n\n\n<li>\u5c06\u5f53\u524d\u8282\u70b9\u7684<strong>\u53f3\u5b50\u6811<\/strong>\u63a5\u5230\u8fd9\u4e2a\u6700\u53f3\u8282\u70b9\u7684\u00a0<code>right<\/code>\u00a0\u4e0a\uff1b<\/li>\n\n\n\n<li>\u5c06<strong>\u6574\u4e2a\u5de6\u5b50\u6811<\/strong>\u79fb\u5230\u5f53\u524d\u8282\u70b9\u7684\u00a0<code>right<\/code>\uff1b<\/li>\n\n\n\n<li>\u5c06\u00a0<code>left<\/code>\u00a0\u7f6e\u4e3a\u00a0<code>null<\/code>\uff1b<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>\u79fb\u52a8\u5230\u4e0b\u4e00\u4e2a\u53f3\u8282\u70b9\uff0c\u91cd\u590d\u4e0a\u8ff0\u8fc7\u7a0b\u3002<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\">\u4e3a\u4ec0\u4e48\u627e\u201c\u5de6\u5b50\u6811\u7684\u6700\u53f3\u8282\u70b9\u201d\uff1f<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u56e0\u4e3a\u5728\u5148\u5e8f\u904d\u5386\u4e2d\uff0c<strong>\u5de6\u5b50\u6811\u7684\u6700\u540e\u4e00\u4e2a\u88ab\u8bbf\u95ee\u7684\u8282\u70b9<\/strong>\uff0c\u5c31\u662f\u5176<strong>\u6700\u53f3\u8def\u5f84\u7684\u672b\u7aef<\/strong>\u3002<\/li>\n\n\n\n<li>\u628a\u539f\u53f3\u5b50\u6811\u63a5\u5728\u8fd9\u91cc\uff0c\u5c31\u80fd\u4fdd\u8bc1\u5148\u5e8f\u987a\u5e8f\u4e0d\u88ab\u7834\u574f\u3002<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>\ud83d\udd17 \u4e8c\u53c9\u6811\u5c55\u5f00\u4e3a\u94fe\u8868 \u9898\u76ee\u6765\u6e90\uff1a114. \u4e8c\u53c9\u6811\u5c55\u5f00\u4e3a\u94fe\u8868 &#8211; \u529b\u6263\uff08LeetCode\uff09 \ud83d\udccc \u9898\u76ee [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[39,12],"tags":[57,58,14],"class_list":["post-446","post","type-post","status-publish","format-standard","hentry","category-binary_tree","category-algorithm","tag-binary_tree","tag-dfs","tag-algorithm"],"_links":{"self":[{"href":"https:\/\/heyingnian.com\/index.php\/wp-json\/wp\/v2\/posts\/446","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/heyingnian.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/heyingnian.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/heyingnian.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/heyingnian.com\/index.php\/wp-json\/wp\/v2\/comments?post=446"}],"version-history":[{"count":1,"href":"https:\/\/heyingnian.com\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions"}],"predecessor-version":[{"id":448,"href":"https:\/\/heyingnian.com\/index.php\/wp-json\/wp\/v2\/posts\/446\/revisions\/448"}],"wp:attachment":[{"href":"https:\/\/heyingnian.com\/index.php\/wp-json\/wp\/v2\/media?parent=446"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/heyingnian.com\/index.php\/wp-json\/wp\/v2\/categories?post=446"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/heyingnian.com\/index.php\/wp-json\/wp\/v2\/tags?post=446"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}