《LeetCode力扣练习》代码随想录——二叉树（把二叉搜索树转换为累加树—Java）

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刷题思路来源于 代码随想录

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538. 把二叉搜索树转换为累加树

• 递归-中序遍历

  /*** Definition for a binary tree node.* public class TreeNode {* int val;* TreeNode left;* TreeNode right;* TreeNode() {}* TreeNode(int val) { this.val = val; }* TreeNode(int val, TreeNode left, TreeNode right) {* this.val = val;* this.left = left;* this.right = right;* }* }*/
  class Solution {private int pre = 0;public TreeNode convertBST(TreeNode root) {recursion(root);return root;}private void recursion(TreeNode root) {if (root == null) {return;}recursion(root.right);root.val = root.val + pre;pre = root.val;recursion(root.left);return;}}
  

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