Range Sum of BST
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].
Example 1
10
/ \
5 15
/ \ \
3 7 18Input
root = [10,5,15,3,7,null,18], low = 7, high = 15Output
32Nodes 7, 10, and 15 are in the range [7, 15], and 7 + 10 + 15 = 32.
Example 2
10
/ \
5 15
/ \ / \
3 7 13 18
/ /
1 6Input
root = [10,5,15,3,7,13,18,1,null,6], low = 6, high = 10Output
23Nodes 6, 7, and 10 are in the range [6, 10], and 6 + 7 + 10 = 23.
Constraints
- The number of nodes in the tree is in the range
[1, 2 * 10^4]. 1 <= Node.val <= 10^51 <= low <= high <= 10^5- All
Node.valare unique.