{ "data": { "question": { "questionId": "1296", "questionFrontendId": "1483", "boundTopicId": null, "title": "Kth Ancestor of a Tree Node", "titleSlug": "kth-ancestor-of-a-tree-node", "content": "

You are given a tree with n nodes numbered from 0 to n - 1 in the form of a parent array parent where parent[i] is the parent of ith node. The root of the tree is node 0. Find the kth ancestor of a given node.

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The kth ancestor of a tree node is the kth node in the path from that node to the root node.

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Implement the TreeAncestor class:

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Example 1:

\n\"\"\n
\nInput\n["TreeAncestor", "getKthAncestor", "getKthAncestor", "getKthAncestor"]\n[[7, [-1, 0, 0, 1, 1, 2, 2]], [3, 1], [5, 2], [6, 3]]\nOutput\n[null, 1, 0, -1]\n\nExplanation\nTreeAncestor treeAncestor = new TreeAncestor(7, [-1, 0, 0, 1, 1, 2, 2]);\ntreeAncestor.getKthAncestor(3, 1); // returns 1 which is the parent of 3\ntreeAncestor.getKthAncestor(5, 2); // returns 0 which is the grandparent of 5\ntreeAncestor.getKthAncestor(6, 3); // returns -1 because there is no such ancestor
\n\n

 

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Constraints:

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null, "__typename": "TopicTagNode" } ], "companyTagStats": null, "codeSnippets": [ { "lang": "C++", "langSlug": "cpp", "code": "class TreeAncestor {\npublic:\n TreeAncestor(int n, vector& parent) {\n \n }\n \n int getKthAncestor(int node, int k) {\n \n }\n};\n\n/**\n * Your TreeAncestor object will be instantiated and called as such:\n * TreeAncestor* obj = new TreeAncestor(n, parent);\n * int param_1 = obj->getKthAncestor(node,k);\n */", "__typename": "CodeSnippetNode" }, { "lang": "Java", "langSlug": "java", "code": "class TreeAncestor {\n\n public TreeAncestor(int n, int[] parent) {\n \n }\n \n public int getKthAncestor(int node, int k) {\n \n }\n}\n\n/**\n * Your TreeAncestor object will be instantiated and called as such:\n * TreeAncestor obj = new TreeAncestor(n, parent);\n * int param_1 = obj.getKthAncestor(node,k);\n */", "__typename": "CodeSnippetNode" }, { "lang": "Python", "langSlug": "python", "code": "class TreeAncestor(object):\n\n def __init__(self, n, parent):\n \"\"\"\n :type n: int\n :type parent: List[int]\n \"\"\"\n \n\n def getKthAncestor(self, node, k):\n \"\"\"\n :type node: int\n :type k: int\n :rtype: int\n \"\"\"\n \n\n\n# Your TreeAncestor object will be instantiated and called as such:\n# obj = TreeAncestor(n, parent)\n# param_1 = obj.getKthAncestor(node,k)", "__typename": "CodeSnippetNode" }, { "lang": "Python3", "langSlug": "python3", "code": "class TreeAncestor:\n\n def __init__(self, n: int, parent: List[int]):\n \n\n def getKthAncestor(self, node: int, k: int) -> int:\n \n\n\n# Your TreeAncestor object will be instantiated and called as such:\n# obj = TreeAncestor(n, parent)\n# param_1 = obj.getKthAncestor(node,k)", "__typename": "CodeSnippetNode" }, { "lang": "C", "langSlug": "c", "code": "\n\n\ntypedef struct {\n \n} TreeAncestor;\n\n\nTreeAncestor* treeAncestorCreate(int n, int* parent, int parentSize) {\n \n}\n\nint treeAncestorGetKthAncestor(TreeAncestor* obj, int node, int k) {\n \n}\n\nvoid treeAncestorFree(TreeAncestor* obj) {\n \n}\n\n/**\n * Your TreeAncestor struct will be instantiated and called as such:\n * TreeAncestor* obj = treeAncestorCreate(n, parent, parentSize);\n * int param_1 = treeAncestorGetKthAncestor(obj, node, k);\n \n * treeAncestorFree(obj);\n*/", "__typename": "CodeSnippetNode" }, { "lang": "C#", "langSlug": "csharp", "code": "public class TreeAncestor {\n\n public TreeAncestor(int n, int[] parent) {\n \n }\n \n public int GetKthAncestor(int node, int k) {\n \n }\n}\n\n/**\n * Your TreeAncestor object will be instantiated and called as such:\n * TreeAncestor obj = new TreeAncestor(n, parent);\n * int param_1 = obj.GetKthAncestor(node,k);\n */", "__typename": "CodeSnippetNode" }, { "lang": "JavaScript", "langSlug": "javascript", "code": "/**\n * @param {number} n\n * @param {number[]} parent\n */\nvar TreeAncestor = function(n, parent) {\n \n};\n\n/** \n * @param {number} node \n * @param {number} k\n * @return {number}\n */\nTreeAncestor.prototype.getKthAncestor = function(node, k) {\n \n};\n\n/** \n * Your TreeAncestor object will be instantiated and called as such:\n * var obj = new TreeAncestor(n, parent)\n * var param_1 = obj.getKthAncestor(node,k)\n */", "__typename": "CodeSnippetNode" }, { "lang": "Ruby", "langSlug": "ruby", "code": "class TreeAncestor\n\n=begin\n :type n: Integer\n :type parent: Integer[]\n=end\n def initialize(n, parent)\n \n end\n\n\n=begin\n :type node: Integer\n :type k: Integer\n :rtype: Integer\n=end\n def get_kth_ancestor(node, k)\n \n end\n\n\nend\n\n# Your TreeAncestor object will be instantiated and called as such:\n# obj = TreeAncestor.new(n, parent)\n# param_1 = obj.get_kth_ancestor(node, k)", "__typename": "CodeSnippetNode" }, { "lang": "Swift", "langSlug": "swift", "code": "\nclass TreeAncestor {\n\n init(_ n: Int, _ parent: [Int]) {\n \n }\n \n func getKthAncestor(_ node: Int, _ k: Int) -> Int {\n \n }\n}\n\n/**\n * Your TreeAncestor object will be instantiated and called as such:\n * let obj = TreeAncestor(n, parent)\n * let ret_1: Int = obj.getKthAncestor(node, k)\n */", "__typename": "CodeSnippetNode" }, { "lang": "Go", "langSlug": "golang", "code": "type TreeAncestor struct {\n \n}\n\n\nfunc Constructor(n int, parent []int) TreeAncestor {\n \n}\n\n\nfunc (this *TreeAncestor) GetKthAncestor(node int, k int) int {\n \n}\n\n\n/**\n * Your TreeAncestor object will be instantiated and called as such:\n * obj := Constructor(n, parent);\n * param_1 := obj.GetKthAncestor(node,k);\n */", "__typename": "CodeSnippetNode" }, { "lang": "Scala", "langSlug": "scala", "code": "class TreeAncestor(_n: Int, _parent: Array[Int]) {\n\n def getKthAncestor(node: Int, k: Int): Int = {\n \n }\n\n}\n\n/**\n * Your TreeAncestor object will be instantiated and called as such:\n * var obj = new TreeAncestor(n, parent)\n * var param_1 = obj.getKthAncestor(node,k)\n */", "__typename": "CodeSnippetNode" }, { "lang": "Kotlin", "langSlug": "kotlin", "code": "class TreeAncestor(n: Int, parent: IntArray) {\n\n fun getKthAncestor(node: Int, k: Int): Int {\n \n }\n\n}\n\n/**\n * Your TreeAncestor object will be instantiated and called as such:\n * var obj = TreeAncestor(n, parent)\n * var param_1 = obj.getKthAncestor(node,k)\n */", "__typename": "CodeSnippetNode" }, { "lang": "Rust", "langSlug": "rust", "code": "struct TreeAncestor {\n\n}\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 TreeAncestor {\n\n fn new(n: i32, parent: Vec) -> Self {\n \n }\n \n fn get_kth_ancestor(&self, node: i32, k: i32) -> i32 {\n \n }\n}\n\n/**\n * Your TreeAncestor object will be instantiated and called as such:\n * let obj = TreeAncestor::new(n, parent);\n * let ret_1: i32 = obj.get_kth_ancestor(node, k);\n */", "__typename": "CodeSnippetNode" }, { "lang": "PHP", "langSlug": "php", "code": "class TreeAncestor {\n /**\n * @param Integer $n\n * @param Integer[] $parent\n */\n function __construct($n, $parent) {\n \n }\n \n /**\n * @param Integer $node\n * @param Integer $k\n * @return Integer\n */\n function getKthAncestor($node, $k) {\n \n }\n}\n\n/**\n * Your TreeAncestor object will be instantiated and called as such:\n * $obj = TreeAncestor($n, $parent);\n * $ret_1 = $obj->getKthAncestor($node, $k);\n */", "__typename": "CodeSnippetNode" }, { "lang": "TypeScript", "langSlug": "typescript", "code": "class TreeAncestor {\n constructor(n: number, parent: number[]) {\n\n }\n\n getKthAncestor(node: number, k: number): number {\n\n }\n}\n\n/**\n * Your TreeAncestor object will be instantiated and called as such:\n * var obj = new TreeAncestor(n, parent)\n * var param_1 = obj.getKthAncestor(node,k)\n */", "__typename": "CodeSnippetNode" }, { "lang": "Racket", "langSlug": "racket", "code": "(define tree-ancestor%\n (class object%\n (super-new)\n\n ; n : exact-integer?\n\n ; parent : (listof exact-integer?)\n (init-field\n n\n parent)\n \n ; get-kth-ancestor : exact-integer? exact-integer? -> exact-integer?\n (define/public (get-kth-ancestor node k)\n\n )))\n\n;; Your tree-ancestor% object will be instantiated and called as such:\n;; (define obj (new tree-ancestor% [n n] [parent parent]))\n;; (define param_1 (send obj get-kth-ancestor node k))", "__typename": "CodeSnippetNode" }, { "lang": "Erlang", "langSlug": "erlang", "code": "-spec tree_ancestor_init_(N :: integer(), Parent :: [integer()]) -> any().\ntree_ancestor_init_(N, Parent) ->\n .\n\n-spec tree_ancestor_get_kth_ancestor(Node :: integer(), K :: integer()) -> integer().\ntree_ancestor_get_kth_ancestor(Node, K) ->\n .\n\n\n%% Your functions will be called as such:\n%% tree_ancestor_init_(N, Parent),\n%% Param_1 = tree_ancestor_get_kth_ancestor(Node, K),\n\n%% tree_ancestor_init_ will be called before every test case, in which you can do some necessary initializations.", "__typename": "CodeSnippetNode" }, { "lang": "Elixir", "langSlug": "elixir", "code": "defmodule 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