feat: 1448. Count Good Nodes in Binary Tree (#39)

Author: onixlas

src/binary_tree/dfs/count_good_nodes_in_binary_tree/__init__.py

@@ -0,0 +1,23 @@
+from structures import TreeNode
+
+
+class Solution:
+    def good_w_max(self, cur_max, root: TreeNode) -> int:
+        if root:
+            counter = 0
+            if root.val >= cur_max:
+                counter += 1
+            cur_max = max(cur_max, root.val)
+            return (
+                counter
+                + self.good_w_max(cur_max, root.left)
+                + self.good_w_max(cur_max, root.right)
+            )
+        return 0
+
+    def goodNodes(self, root: TreeNode) -> int:
+        return (
+            1
+            + self.good_w_max(root.val, root.left)
+            + self.good_w_max(root.val, root.right)
+        )

src/binary_tree/dfs/count_good_nodes_in_binary_tree/solution.py

@@ -0,0 +1,13 @@
+import pytest
+from src.binary_tree.dfs.count_good_nodes_in_binary_tree.solution import Solution
+from test_utils import TreeBuilder
+
+
+@pytest.mark.parametrize(
+    "root, expected",
+    [([3, 1, 4, 3, None, 1, 5], 4), ([3, 3, None, 4, 2], 3), ([1], 1)],
+)
+def test_max_depth(root, expected):
+    root = TreeBuilder.from_list(root)
+    solution = Solution()
+    assert solution.goodNodes(root) == expected