Time: 36 ms (70.96%), Space: 16.5 MB (38.65%) - LeetHub

Author: hogan-tech

0979-distribute-coins-in-binary-tree/0979-distribute-coins-in-binary-tree.py

@@ -0,0 +1,31 @@
+# time complexity: O(n)
+# space complexity: O(n)
+from typing import Optional
+
+
+class TreeNode:
+    def __init__(self, val=0, left=None, right=None):
+        self.val = val
+        self.left = left
+        self.right = right
+
+
+class Solution:
+    def distributeCoins(self, root: Optional[TreeNode]) -> int:
+        self.moves = 0
+
+        def dfs(node: Optional[TreeNode]):
+            if not node:
+                return 0
+            leftBal = dfs(node.left)
+            rightBal = dfs(node.right)
+            self.moves += abs(leftBal) + abs(rightBal)
+            return node.val + leftBal + rightBal - 1
+        dfs(root)
+        return self.moves
+
+
+root = TreeNode(3)
+root.left = TreeNode(0)
+root.right = TreeNode(0)
+print(Solution().distributeCoins(root))