938. Range Sum of BST

Difficulty: Easy
42 / 42 test cases passed.
Runtime: 316 ms
Memory Usage: 21.7 MB

Author: YuriSpiridonov

Easy/938.RangeSumofBST.py

@@ -0,0 +1,31 @@
+"""
+    Given the root node of a binary search tree, return the sum of values of 
+    all nodes with value between L and R (inclusive).
+    The binary search tree is guaranteed to have unique values.
+
+    Example:
+    Input: root = [10,5,15,3,7,null,18], L = 7, R = 15
+    Output: 32
+
+    Note:
+        1. The number of nodes in the tree is at most 10000.
+        2. The final answer is guaranteed to be less than 2^31.
+"""
+#Difficulty: Easy
+#42 / 42 test cases passed.
+#Runtime: 316 ms
+#Memory Usage: 21.7 MB
+
+#Runtime: 316 ms, faster than 20.89% of Python3 online submissions for Range Sum of BST.
+#Memory Usage: 21.7 MB, less than 94.93% of Python3 online submissions for Range Sum of BST.
+
+class Solution:
+    def rangeSumBST(self, root: TreeNode, L: int, R: int) -> int:
+        summ = 0
+        if not root:
+            return 0
+        if L <= root.val <= R:
+            summ += root.val
+        summ += self.rangeSumBST(root.left, L, R)
+        summ += self.rangeSumBST(root.right, L, R)
+        return summ