Given the root of a binary tree, return the lowest common ancestor of its deepest leaves.
Recall that:
\n\n0. if the depth of a node is d, the depth of each of its children is d + 1.S of nodes, is the node A with the largest depth such that every node in S is in the subtree with root A.\n
Example 1:
\n![\"\"](\"https://s3-lc-upload.s3.amazonaws.com/uploads/2018/07/01/sketch1.png\")
\n\nInput: root = [3,5,1,6,2,0,8,null,null,7,4]\nOutput: [2,7,4]\nExplanation: We return the node with value 2, colored in yellow in the diagram.\nThe nodes coloured in blue are the deepest leaf-nodes of the tree.\nNote that nodes 6, 0, and 8 are also leaf nodes, but the depth of them is 2, but the depth of nodes 7 and 4 is 3.\n\n
Example 2:
\n\n\nInput: root = [1]\nOutput: [1]\nExplanation: The root is the deepest node in the tree, and it's the lca of itself.\n\n\n
Example 3:
\n\n\nInput: root = [0,1,3,null,2]\nOutput: [2]\nExplanation: The deepest leaf node in the tree is 2, the lca of one node is itself.\n\n\n
\n
Constraints:
\n\n[1, 1000].0 <= Node.val <= 1000\n
Note: This question is the same as 865: https://leetcode.com/problems/smallest-subtree-with-all-the-deepest-nodes/
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{\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Go", "langSlug": "golang", "code": "/**\n * Definition for a binary tree node.\n * type TreeNode struct {\n * Val int\n * Left *TreeNode\n * Right *TreeNode\n * }\n */\nfunc lcaDeepestLeaves(root *TreeNode) *TreeNode {\n \n}", "__typename": "CodeSnippetNode" }, { "lang": "Scala", "langSlug": "scala", "code": "/**\n * Definition for a binary tree node.\n * class TreeNode(_value: Int = 0, _left: TreeNode = null, _right: TreeNode = null) {\n * var value: Int = _value\n * var left: TreeNode = _left\n * var right: TreeNode = _right\n * }\n */\nobject Solution {\n def lcaDeepestLeaves(root: TreeNode): TreeNode = {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Kotlin", "langSlug": "kotlin", "code": "/**\n * Example:\n * var ti = TreeNode(5)\n * var v = ti.`val`\n * Definition for a binary tree node.\n * class TreeNode(var `val`: Int) {\n * var left: TreeNode? = null\n * var right: TreeNode? = null\n * }\n */\nclass Solution {\n fun lcaDeepestLeaves(root: TreeNode?): TreeNode? 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Your code is compiled with level two optimization (-O2). AddressSanitizer is also enabled to help detect out-of-bounds and use-after-free bugs.
Most standard library headers are already included automatically for your convenience.
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Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms
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