938. Range Sum of BST

Python

class Solution:
    def __init__(self):
        self.result = 0
    def rangeSumBST(self, root: Optional[TreeNode], low: int, high: int) -> int:
        self.result = 0
        self._travel(root, low, high)
        return self.result

    def _travel(self, node, low, high):
        if not node:
            return

        if node.val > low:
            self._travel(node.left, low, high)

        if low <= node.val and node.val <= high:
            self.result += node.val

        if node.val < high:
            self._travel(node.right, low, high)
Python​

Python
