[코테 풀이] Range Sum of BST

Q_938) Range Sum of BST

출처 : https://leetcode.com/problems/range-sum-of-bst/submissions/

Given the root node of a binary search tree and two integers low and high, return the sum of values of all nodes with a value in the inclusive range [low, high].

/**
 * 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 {
    public int rangeSumBST(TreeNode root, int low, int high) {
        if (root == null) return 0;
        int sum = 0;

        if (low <= root.val && root.val <= high) {
            sum += root.val;
        }

        sum += rangeSumBST(root.left, low, high);
        sum += rangeSumBST(root.right, low, high);
        return sum;


    }
}

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