{"id":947,"date":"2025-12-12T20:03:10","date_gmt":"2025-12-12T12:03:10","guid":{"rendered":"https:\/\/www.guanhaobo.cn\/?p=947"},"modified":"2025-12-12T20:03:10","modified_gmt":"2025-12-12T12:03:10","slug":"leetcode-199-%e4%ba%8c%e5%8f%89%e6%a0%91%e7%9a%84%e5%8f%b3%e8%a7%86%e5%9b%be","status":"publish","type":"post","link":"https:\/\/www.guanhaobo.cn\/?p=947","title":{"rendered":"LeetCode 199 \u2014 \u4e8c\u53c9\u6811\u7684\u53f3\u89c6\u56fe"},"content":{"rendered":"

\u9898\u76ee\u63cf\u8ff0<\/h1>\n

\u7ed9\u5b9a\u4e00\u4e2a\u4e8c\u53c9\u6811\u7684 \u6839\u8282\u70b9 root\uff0c\u60f3\u8c61\u81ea\u5df1\u7ad9\u5728\u5b83\u7684\u53f3\u4fa7\uff0c\u6309\u7167\u4ece\u9876\u90e8\u5230\u5e95\u90e8\u7684\u987a\u5e8f\uff0c\u8fd4\u56de\u4ece\u53f3\u4fa7\u6240\u80fd\u770b\u5230\u7684\u8282\u70b9\u503c\u3002<\/p>\n

\"\"<\/a><\/p>\n

\u9898\u76ee\u5206\u6790<\/h1>\n

\u8fed\u4ee3<\/h2>\n

\u4f7f\u7528\u961f\u5217\uff0c\u5c42\u5e8f\u904d\u5386\uff0c\u8bb0\u5f55\u6bcf\u5c42\u7684\u6570\u91cf\uff0c\u5728\u6bcf\u5c42\u5bf9\u540e\u4e00\u4e2a\u6570\u5b57\u51fa\u961f\u65f6\uff0c\u8bb0\u5f55\u4e0b\u6765<\/p>\n

\u9012\u5f52<\/h2>\n

\u6309\u7167 \u4e2d -> \u53f3 -> \u5de6 \u7684\u987a\u5e8f\u8fdb\u884c\u9012\u5f52\u904d\u5386\uff0c\u7ef4\u62a4\u5f53\u524d\u7684\u6df1\u5ea6\uff0c\u5f53\u6df1\u5ea6\u5927\u4e8e\u7ed3\u679c\u7684\u5927\u5c0f\u65f6\uff0c\u8bf4\u660e\u662f\u7b2c\u4e00\u6b21\u6765\u5230\u8fd9\u4e2a\u5c42\u7ea7\uff0c\u4e14\u662f\u6700\u53f3\u4fa7\u5148\u904d\u5386\uff0c\u6240\u4ee5\u628a\u5f53\u524d\u503c\u52a0\u5165\u7ed3\u679c\u4e2d<\/p>\n

Java<\/h1>\n
public List<Integer> rightSideView(TreeNode root) {\n    List<Integer> ans = new ArrayList<>();\n    dfs(root, ans, 1);\n    return ans;\n}\n\nprivate void dfs(TreeNode root, List<Integer> ans, int depth) {\n    if (root == null) {\n        return;\n    }\n    if (depth > ans.size()) {\n        ans.add(root.val);\n    }\n    dfs(root.right, ans, depth + 1);\n    dfs(root.left, ans, depth + 1);\n}\n<\/code><\/pre>\n
Kotlin<\/h1>\n
fun rightSideView(root: TreeNode?): List<Int> {\n    val queue = LinkedList<TreeNode>()\n    val ans = ArrayList<Int>()\n    if (root == null) {\n        return ans\n    }\n    queue.offer(root)\n    while (!queue.isEmpty()) {\n        var size = queue.size\n        while (size > 0) {\n            val node = queue.poll()\n            if (node.left != null) {\n                queue.offer(node.left)\n            }\n            if (node.right != null) {\n                queue.offer(node.right)\n            }\n            if (size == 1) {\n                ans.add(node.`val`)\n            }\n            size--\n        }\n    }\n    return ans\n}\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"
\u9898\u76ee\u63cf\u8ff0 \u7ed9\u5b9a\u4e00\u4e2a\u4e8c\u53c9\u6811\u7684 \u6839\u8282\u70b9 root\uff0c\u60f3\u8c61\u81ea\u5df1\u7ad9\u5728\u5b83\u7684\u53f3\u4fa7\uff0c\u6309\u7167\u4ece\u9876\u90e8\u5230\u5e95\u90e8\u7684\u987a\u5e8f\uff0c\u8fd4\u56de\u4ece\u53f3\u4fa7\u6240\u80fd\u770b\u5230 […]<\/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":[88,11,20,33,64,87],"class_list":["post-947","post","type-post","status-publish","format-standard","hentry","category-algo","tag-bfs","tag-dfs","tag-leetcode","tag-33","tag-64","tag-87"],"_links":{"self":[{"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/posts\/947","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=947"}],"version-history":[{"count":1,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/posts\/947\/revisions"}],"predecessor-version":[{"id":948,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=\/wp\/v2\/posts\/947\/revisions\/948"}],"wp:attachment":[{"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=947"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=947"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.guanhaobo.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=947"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}