Package g0501_0600.s0538_convert_bst_to_greater_tree

Class Solution

java.lang.Object
g0501_0600.s0538_convert_bst_to_greater_tree.Solution
public class Solution extends Object
538 - Convert BST to Greater Tree.<p>Medium</p> <p>Given the <code>root</code> of a Binary Search Tree (BST), convert it to a Greater Tree such that every key of the original BST is changed to the original key plus the sum of all keys greater than the original key in BST.</p> <p>As a reminder, a <em>binary search tree</em> is a tree that satisfies these constraints:</p> <ul> <li>The left subtree of a node contains only nodes with keys <strong>less than</strong> the node&rsquo;s key.</li> <li>The right subtree of a node contains only nodes with keys <strong>greater than</strong> the node&rsquo;s key.</li> <li>Both the left and right subtrees must also be binary search trees.</li> </ul> <p><strong>Example 1:</strong></p> <p><img src="https://assets.leetcode.com/uploads/2019/05/02/tree.png" alt="" /></p> <p><strong>Input:</strong> root = [4,1,6,0,2,5,7,null,null,null,3,null,null,null,8]</p> <p><strong>Output:</strong> [30,36,21,36,35,26,15,null,null,null,33,null,null,null,8]</p> <p><strong>Example 2:</strong></p> <p><strong>Input:</strong> root = [0,null,1]</p> <p><strong>Output:</strong> [1,null,1]</p> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in the tree is in the range <code>[0, 10<sup>4</sup>]</code>.</li> <li><code>-10<sup>4</sup> <= Node.val <= 10<sup>4</sup></code></li> <li>All the values in the tree are <strong>unique</strong>.</li> <li><code>root</code> is guaranteed to be a valid binary search tree.</li> </ul> <p><strong>Note:</strong> This question is the same as 1038: <a href="https://leetcode.com/problems/binary-search-tree-to-greater-sum-tree/" target="_top">https://leetcode.com/problems/binary-search-tree-to-greater-sum-tree/</a></p>

  • Constructor Details

    • Solution

      public Solution()

  • Method Details