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            "title": "Binary Tree Pruning",
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            "content": "<p>Given the <code>root</code> of a binary tree, return <em>the same tree where every subtree (of the given tree) not containing a </em><code>1</code><em> has been removed</em>.</p>\n\n<p>A subtree of a node <code>node</code> is <code>node</code> plus every node that is a descendant of <code>node</code>.</p>\n\n<p>&nbsp;</p>\n<p><strong>Example 1:</strong></p>\n<img alt=\"\" src=\"https://s3-lc-upload.s3.amazonaws.com/uploads/2018/04/06/1028_2.png\" style=\"width: 500px; height: 140px;\" />\n<pre>\n<strong>Input:</strong> root = [1,null,0,0,1]\n<strong>Output:</strong> [1,null,0,null,1]\n<strong>Explanation:</strong> \nOnly the red nodes satisfy the property &quot;every subtree not containing a 1&quot;.\nThe diagram on the right represents the answer.\n</pre>\n\n<p><strong>Example 2:</strong></p>\n<img alt=\"\" src=\"https://s3-lc-upload.s3.amazonaws.com/uploads/2018/04/06/1028_1.png\" style=\"width: 500px; height: 115px;\" />\n<pre>\n<strong>Input:</strong> root = [1,0,1,0,0,0,1]\n<strong>Output:</strong> [1,null,1,null,1]\n</pre>\n\n<p><strong>Example 3:</strong></p>\n<img alt=\"\" src=\"https://s3-lc-upload.s3.amazonaws.com/uploads/2018/04/05/1028.png\" style=\"width: 500px; height: 134px;\" />\n<pre>\n<strong>Input:</strong> root = [1,1,0,1,1,0,1,0]\n<strong>Output:</strong> [1,1,0,1,1,null,1]\n</pre>\n\n<p>&nbsp;</p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li>The number of nodes in the tree is in the range <code>[1, 200]</code>.</li>\n\t<li><code>Node.val</code> is either <code>0</code> or <code>1</code>.</li>\n</ul>\n",
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                    "name": "Tree",
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                    "name": "Depth-First Search",
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                    "name": "Binary Tree",
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                    "lang": "C++",
                    "langSlug": "cpp",
                    "code": "/**\n * Definition for a binary tree node.\n * struct TreeNode {\n *     int val;\n *     TreeNode *left;\n *     TreeNode *right;\n *     TreeNode() : val(0), left(nullptr), right(nullptr) {}\n *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}\n *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}\n * };\n */\nclass Solution {\npublic:\n    TreeNode* pruneTree(TreeNode* root) {\n        \n    }\n};",
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                    "lang": "Java",
                    "langSlug": "java",
                    "code": "/**\n * Definition for a binary tree node.\n * public class TreeNode {\n *     int val;\n *     TreeNode left;\n *     TreeNode right;\n *     TreeNode() {}\n *     TreeNode(int val) { this.val = val; }\n *     TreeNode(int val, TreeNode left, TreeNode right) {\n *         this.val = val;\n *         this.left = left;\n *         this.right = right;\n *     }\n * }\n */\nclass Solution {\n    public TreeNode pruneTree(TreeNode root) {\n        \n    }\n}",
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                    "lang": "Python",
                    "langSlug": "python",
                    "code": "# Definition for a binary tree node.\n# class TreeNode(object):\n#     def __init__(self, val=0, left=None, right=None):\n#         self.val = val\n#         self.left = left\n#         self.right = right\nclass Solution(object):\n    def pruneTree(self, root):\n        \"\"\"\n        :type root: Optional[TreeNode]\n        :rtype: Optional[TreeNode]\n        \"\"\"\n        ",
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                    "lang": "Python3",
                    "langSlug": "python3",
                    "code": "# Definition for a binary tree node.\n# class TreeNode:\n#     def __init__(self, val=0, left=None, right=None):\n#         self.val = val\n#         self.left = left\n#         self.right = right\nclass Solution:\n    def pruneTree(self, root: Optional[TreeNode]) -> Optional[TreeNode]:\n        ",
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                    "lang": "C",
                    "langSlug": "c",
                    "code": "/**\n * Definition for a binary tree node.\n * struct TreeNode {\n *     int val;\n *     struct TreeNode *left;\n *     struct TreeNode *right;\n * };\n */\n\n\nstruct TreeNode* pruneTree(struct TreeNode* root){\n\n}",
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                    "lang": "C#",
                    "langSlug": "csharp",
                    "code": "/**\n * Definition for a binary tree node.\n * public class TreeNode {\n *     public int val;\n *     public TreeNode left;\n *     public TreeNode right;\n *     public TreeNode(int val=0, TreeNode left=null, TreeNode right=null) {\n *         this.val = val;\n *         this.left = left;\n *         this.right = right;\n *     }\n * }\n */\npublic class Solution {\n    public TreeNode PruneTree(TreeNode root) {\n        \n    }\n}",
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                {
                    "lang": "JavaScript",
                    "langSlug": "javascript",
                    "code": "/**\n * Definition for a binary tree node.\n * function TreeNode(val, left, right) {\n *     this.val = (val===undefined ? 0 : val)\n *     this.left = (left===undefined ? null : left)\n *     this.right = (right===undefined ? null : right)\n * }\n */\n/**\n * @param {TreeNode} root\n * @return {TreeNode}\n */\nvar pruneTree = function(root) {\n    \n};",
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                    "lang": "Ruby",
                    "langSlug": "ruby",
                    "code": "# Definition for a binary tree node.\n# class TreeNode\n#     attr_accessor :val, :left, :right\n#     def initialize(val = 0, left = nil, right = nil)\n#         @val = val\n#         @left = left\n#         @right = right\n#     end\n# end\n# @param {TreeNode} root\n# @return {TreeNode}\ndef prune_tree(root)\n    \nend",
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                    "lang": "Swift",
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                    "code": "/**\n * Definition for a binary tree node.\n * public class TreeNode {\n *     public var val: Int\n *     public var left: TreeNode?\n *     public var right: TreeNode?\n *     public init() { self.val = 0; self.left = nil; self.right = nil; }\n *     public init(_ val: Int) { self.val = val; self.left = nil; self.right = nil; }\n *     public init(_ val: Int, _ left: TreeNode?, _ right: TreeNode?) {\n *         self.val = val\n *         self.left = left\n *         self.right = right\n *     }\n * }\n */\nclass Solution {\n    func pruneTree(_ root: TreeNode?) -> TreeNode? {\n        \n    }\n}",
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                {
                    "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 pruneTree(root *TreeNode) *TreeNode {\n    \n}",
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                    "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 pruneTree(root: TreeNode): TreeNode = {\n        \n    }\n}",
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                    "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 pruneTree(root: TreeNode?): TreeNode? {\n        \n    }\n}",
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                    "lang": "Rust",
                    "langSlug": "rust",
                    "code": "// Definition for a binary tree node.\n// #[derive(Debug, PartialEq, Eq)]\n// pub struct TreeNode {\n//   pub val: i32,\n//   pub left: Option<Rc<RefCell<TreeNode>>>,\n//   pub right: Option<Rc<RefCell<TreeNode>>>,\n// }\n// \n// impl TreeNode {\n//   #[inline]\n//   pub fn new(val: i32) -> Self {\n//     TreeNode {\n//       val,\n//       left: None,\n//       right: None\n//     }\n//   }\n// }\nuse std::rc::Rc;\nuse std::cell::RefCell;\nimpl Solution {\n    pub fn prune_tree(root: Option<Rc<RefCell<TreeNode>>>) -> Option<Rc<RefCell<TreeNode>>> {\n        \n    }\n}",
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                    "code": "/**\n * Definition for a binary tree node.\n * class TreeNode {\n *     public $val = null;\n *     public $left = null;\n *     public $right = null;\n *     function __construct($val = 0, $left = null, $right = null) {\n *         $this->val = $val;\n *         $this->left = $left;\n *         $this->right = $right;\n *     }\n * }\n */\nclass Solution {\n\n    /**\n     * @param TreeNode $root\n     * @return TreeNode\n     */\n    function pruneTree($root) {\n        \n    }\n}",
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                    "lang": "TypeScript",
                    "langSlug": "typescript",
                    "code": "/**\n * Definition for a binary tree node.\n * class TreeNode {\n *     val: number\n *     left: TreeNode | null\n *     right: TreeNode | null\n *     constructor(val?: number, left?: TreeNode | null, right?: TreeNode | null) {\n *         this.val = (val===undefined ? 0 : val)\n *         this.left = (left===undefined ? null : left)\n *         this.right = (right===undefined ? null : right)\n *     }\n * }\n */\n\nfunction pruneTree(root: TreeNode | null): TreeNode | null {\n\n};",
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                    "code": "; Definition for a binary tree node.\n#|\n\n; val : integer?\n; left : (or/c tree-node? #f)\n; right : (or/c tree-node? #f)\n(struct tree-node\n  (val left right) #:mutable #:transparent)\n\n; constructor\n(define (make-tree-node [val 0])\n  (tree-node val #f #f))\n\n|#\n\n(define/contract (prune-tree root)\n  (-> (or/c tree-node? #f) (or/c tree-node? #f))\n\n  )",
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                    "lang": "Erlang",
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                    "code": "%% Definition for a binary tree node.\n%%\n%% -record(tree_node, {val = 0 :: integer(),\n%%                     left = null  :: 'null' | #tree_node{},\n%%                     right = null :: 'null' | #tree_node{}}).\n\n-spec prune_tree(Root :: #tree_node{} | null) -> #tree_node{} | null.\nprune_tree(Root) ->\n  .",
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