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Range Sum of BST

Given the root of a BST (as a level-order array) and two integers low and high, return the sum of all node values in the inclusive range [low, high].

Example:

Input:

10,5,15,3,7,null,18
7
15

Output:

Reasoning:

The given level-order array represents a Binary Search Tree (BST) with the following structure:
- Root: 10
- Left child: 5
- Right child: 15
- Left grandchild of root: 3 (left child of 5)
- Right grandchild of root: 7 (right child of 5)
- Right grandchild of root: 18 (right child of 15)
We traverse the BST and consider node values within the range $[7, 15]$
The node values within this range are 7, 10, and 15, so we calculate the sum: $7 + 10 + 15 = 32$
The final output is the sum of these node values, which is 32

Constraints:

1 <= number of nodes <= 2 * 10^4
1 <= Node.val <= 10^5
1 <= low <= high <= 10^5

Editor

Python 3.13.1

Test Results

0/0

Run code to see test results.

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