62 lines
1.2 KiB
JavaScript
62 lines
1.2 KiB
JavaScript
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/*
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* @lc app=leetcode id=538 lang=javascript
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*
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* [538] Convert BST to Greater Tree
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*
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* https://leetcode.com/problems/convert-bst-to-greater-tree/description/
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*
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* algorithms
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* Easy (50.04%)
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* Total Accepted: 75.4K
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* Total Submissions: 149K
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* Testcase Example: '[5,2,13]'
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*
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* Given a Binary Search Tree (BST), convert it to a Greater Tree such that
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* every key of the original BST is changed to the original key plus sum of all
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* keys greater than the original key in BST.
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*
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*
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* Example:
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*
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* Input: The root of a Binary Search Tree like this:
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* 5
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* / \
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* 2 13
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*
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* Output: The root of a Greater Tree like this:
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* 18
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* / \
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* 20 13
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*
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*
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*/
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/**
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* Definition for a binary tree node.
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* function TreeNode(val) {
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* this.val = val;
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* this.left = this.right = null;
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* }
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*/
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/**
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* @param {TreeNode} root
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* @return {TreeNode}
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*/
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var convertBST = function(root) {
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let res = 0;
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function r(root) {
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if (root === null) return null;
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r(root.right);
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root.val += res;
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res = +root.val;
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r(root.left);
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return root;
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}
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r(root);
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return root;
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};
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