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"title": "Serialize and Deserialize BST",
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"content": "<p>Serialization is converting a data structure or object into a sequence of bits so that it can be stored in a file or memory buffer, or transmitted across a network connection link to be reconstructed later in the same or another computer environment.</p>\n\n<p>Design an algorithm to serialize and deserialize a <b>binary search tree</b>. There is no restriction on how your serialization/deserialization algorithm should work. You need to ensure that a binary search tree can be serialized to a string, and this string can be deserialized to the original tree structure.</p>\n\n<p><b>The encoded string should be as compact as possible.</b></p>\n\n<p> </p>\n<p><strong class=\"example\">Example 1:</strong></p>\n<pre><strong>Input:</strong> root = [2,1,3]\n<strong>Output:</strong> [2,1,3]\n</pre><p><strong class=\"example\">Example 2:</strong></p>\n<pre><strong>Input:</strong> root = []\n<strong>Output:</strong> []\n</pre>\n<p> </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>[0, 10<sup>4</sup>]</code>.</li>\n\t<li><code>0 <= Node.val <= 10<sup>4</sup></code></li>\n\t<li>The input tree is <strong>guaranteed</strong> to be a binary search tree.</li>\n</ul>\n",
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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(int x) : val(x), left(NULL), right(NULL) {}\n * };\n */\nclass Codec {\npublic:\n\n // Encodes a tree to a single string.\n string serialize(TreeNode* root) {\n \n }\n\n // Decodes your encoded data to tree.\n TreeNode* deserialize(string data) {\n \n }\n};\n\n// Your Codec object will be instantiated and called as such:\n// Codec* ser = new Codec();\n// Codec* deser = new Codec();\n// string tree = ser->serialize(root);\n// TreeNode* ans = deser->deserialize(tree);\n// return ans;",
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"code": "/**\n * Definition for a binary tree node.\n * public class TreeNode {\n * int val;\n * TreeNode left;\n * TreeNode right;\n * TreeNode(int x) { val = x; }\n * }\n */\npublic class Codec {\n\n // Encodes a tree to a single string.\n public String serialize(TreeNode root) {\n \n }\n\n // Decodes your encoded data to tree.\n public TreeNode deserialize(String data) {\n \n }\n}\n\n// Your Codec object will be instantiated and called as such:\n// Codec ser = new Codec();\n// Codec deser = new Codec();\n// String tree = ser.serialize(root);\n// TreeNode ans = deser.deserialize(tree);\n// return ans;",
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"lang": "Python",
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"code": "# Definition for a binary tree node.\n# class TreeNode(object):\n# def __init__(self, x):\n# self.val = x\n# self.left = None\n# self.right = None\n\nclass Codec:\n\n def serialize(self, root):\n \"\"\"Encodes a tree to a single string.\n \n :type root: TreeNode\n :rtype: str\n \"\"\"\n \n\n def deserialize(self, data):\n \"\"\"Decodes your encoded data to tree.\n \n :type data: str\n :rtype: TreeNode\n \"\"\"\n \n\n# Your Codec object will be instantiated and called as such:\n# ser = Codec()\n# deser = Codec()\n# tree = ser.serialize(root)\n# ans = deser.deserialize(tree)\n# return ans",
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"code": "# Definition for a binary tree node.\n# class TreeNode:\n# def __init__(self, x):\n# self.val = x\n# self.left = None\n# self.right = None\n\nclass Codec:\n\n def serialize(self, root: Optional[TreeNode]) -> str:\n \"\"\"Encodes a tree to a single string.\n \"\"\"\n \n\n def deserialize(self, data: str) -> Optional[TreeNode]:\n \"\"\"Decodes your encoded data to tree.\n \"\"\"\n \n\n# Your Codec object will be instantiated and called as such:\n# Your Codec object will be instantiated and called as such:\n# ser = Codec()\n# deser = Codec()\n# tree = ser.serialize(root)\n# ans = deser.deserialize(tree)\n# return ans",
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"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/** Encodes a tree to a single string. */\nchar* serialize(struct TreeNode* root) {\n \n}\n\n/** Decodes your encoded data to tree. */\nstruct TreeNode* deserialize(char* data) {\n \n}\n\n// Your functions will be called as such:\n// char* data = serialize(root);\n// deserialize(data);",
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"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 x) { val = x; }\n * }\n */\npublic class Codec {\n\n // Encodes a tree to a single string.\n public string serialize(TreeNode root) {\n \n }\n\n // Decodes your encoded data to tree.\n public TreeNode deserialize(string data) {\n \n }\n}\n\n// Your Codec object will be instantiated and called as such:\n// Codec ser = new Codec();\n// Codec deser = new Codec();\n// String tree = ser.serialize(root);\n// TreeNode ans = deser.deserialize(tree);\n// return ans;",
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"lang": "JavaScript",
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"code": "/**\n * Definition for a binary tree node.\n * function TreeNode(val) {\n * this.val = val;\n * this.left = this.right = null;\n * }\n */\n\n/**\n * Encodes a tree to a single string.\n *\n * @param {TreeNode} root\n * @return {string}\n */\nvar serialize = function(root) {\n \n};\n\n/**\n * Decodes your encoded data to tree.\n *\n * @param {string} data\n * @return {TreeNode}\n */\nvar deserialize = function(data) {\n \n};\n\n/**\n * Your functions will be called as such:\n * deserialize(serialize(root));\n */",
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"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\n/*\n * Encodes a tree to a single string.\n */\nfunction serialize(root: TreeNode | null): string {\n\n};\n\n/*\n * Decodes your encoded data to tree.\n */\nfunction deserialize(data: string): TreeNode | null {\n\n};\n\n\n/**\n * Your functions will be called as such:\n * deserialize(serialize(root));\n */",
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"lang": "PHP",
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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 $right = null;\n * function __construct($value) { $this->val = $value; }\n * }\n */\n\nclass Codec {\n function __construct() {\n \n }\n \n /**\n * @param TreeNode $root\n * @return String\n */\n function serialize($root) {\n \n }\n \n /**\n * @param String $data\n * @return TreeNode\n */\n function deserialize($data) {\n \n }\n}\n\n/**\n * Your Codec object will be instantiated and called as such:\n * $ser = new Codec();\n * $tree = $ser->serialize($param_1);\n * $deser = new Codec();\n * $ret = $deser->deserialize($tree);\n * return $ret;\n */",
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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(_ val: Int) {\n * self.val = val\n * self.left = nil\n * self.right = nil\n * }\n * }\n */\n\nclass Codec {\n // Encodes a tree to a single string.\n func serialize(_ root: TreeNode?) -> String {\n \n }\n \n // Decodes your encoded data to tree.\n func deserialize(_ data: String) -> TreeNode? {\n \n }\n}\n\n/**\n * Your Codec object will be instantiated and called as such:\n * let ser = Codec()\n * let deser = Codec()\n * let tree: String = ser.serialize(root)\n * let ans = deser.deserialize(tree)\n * return ans\n*/",
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"code": "/**\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 */\n\nclass Codec() {\n\t// Encodes a tree to a single string.\n fun serialize(root: TreeNode?): String {\n \n }\n\n // Decodes your encoded data to tree.\n fun deserialize(data: String): TreeNode? {\n \n }\n}\n\n/**\n * Your Codec object will be instantiated and called as such:\n * val ser = Codec()\n * val deser = Codec()\n * val tree: String = ser.serialize(root)\n * val ans = deser.deserialize(tree)\n * return ans\n */",
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"lang": "Go",
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"code": "/**\n * Definition for a binary tree node.\n * type TreeNode struct {\n * Val int\n * Left *TreeNode\n * Right *TreeNode\n * }\n */\n\ntype Codec struct {\n \n}\n\nfunc Constructor() Codec {\n \n}\n\n// Serializes a tree to a single string.\nfunc (this *Codec) serialize(root *TreeNode) string {\n \n}\n\n// Deserializes your encoded data to tree.\nfunc (this *Codec) deserialize(data string) *TreeNode { \n \n}\n\n\n/**\n * Your Codec object will be instantiated and called as such:\n * ser := Constructor()\n * deser := Constructor()\n * tree := ser.serialize(root)\n * ans := deser.deserialize(tree)\n * return ans\n */",
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"lang": "Ruby",
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"code": "# Definition for a binary tree node.\n# class TreeNode\n# attr_accessor :val, :left, :right\n# def initialize(val)\n# @val = val\n# @left, @right = nil, nil\n# end\n# end\n\n# Encodes a tree to a single string.\n#\n# @param {TreeNode} root\n# @return {string}\ndef serialize(root)\n \nend\n\n# Decodes your encoded data to tree.\n#\n# @param {string} data\n# @return {TreeNode}\ndef deserialize(data)\n \nend\n\n\n# Your functions will be called as such:\n# deserialize(serialize(data))",
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"code": "/**\n * Definition for a binary tree node.\n * class TreeNode(var _value: Int) {\n * var value: Int = _value\n * var left: TreeNode = null\n * var right: TreeNode = null\n * }\n */\n\nclass Codec {\n // Encodes a tree to a single string.\n def serialize(root: TreeNode): String = {\n \n }\n \n // Decodes your encoded data to tree.\n def deserialize(data: String): TreeNode = {\n \n }\n}\n\n/**\n * Your Codec object will be instantiated and called as such:\n * val ser = new Codec()\n * val deser = new Codec()\n * val tree: String = ser.serialize(root)\n * val ans = deser.deserialize(tree)\n * return ans\n */",
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"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;\nstruct Codec {\n\t\n}\n\n/** \n * `&self` means the method takes an immutable reference.\n * If you need a mutable reference, change it to `&mut self` instead.\n */\nimpl Codec {\n fn new() -> Self {\n \n }\n\n fn serialize(&self, root: Option<Rc<RefCell<TreeNode>>>) -> String {\n \n }\n\t\n fn deserialize(&self, data: String) -> Option<Rc<RefCell<TreeNode>>> {\n \n }\n}\n\n/**\n * Your Codec object will be instantiated and called as such:\n * let obj = Codec::new();\n * let data: String = obj.serialize(strs);\n * let ans: Option<Rc<RefCell<TreeNode>>> = obj.deserialize(data);\n */",
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For the latest Python, please choose Python3 instead.</p>\"], \"c\": [\"C\", \"<p>Compiled with <code>gcc 8.2</code> using the gnu11 standard.</p>\\r\\n\\r\\n<p>Your code is compiled with level one optimization (<code>-O1</code>). <a href=\\\"https://github.com/google/sanitizers/wiki/AddressSanitizer\\\" target=\\\"_blank\\\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\\r\\n\\r\\n<p>Most standard library headers are already included automatically for your convenience.</p>\\r\\n\\r\\n<p>For hash table operations, you may use <a href=\\\"https://troydhanson.github.io/uthash/\\\" target=\\\"_blank\\\">uthash</a>. \\\"uthash.h\\\" is included by default. Below are some examples:</p>\\r\\n\\r\\n<p><b>1. 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