Time: 411 ms (5.01%) | Memory: 21.6 MB (92.64%) - LeetSync

Author: joshua-dierickse-alt

236-lowest-common-ancestor-of-a-binary-tree/lowest-common-ancestor-of-a-binary-tree.py

@@ -0,0 +1,33 @@
+# Definition for a binary tree node.
+# class TreeNode:
+#     def __init__(self, x):
+#         self.val = x
+#         self.left = None
+#         self.right = None
+
+
+def dfs(node, s):
+    if not node:
+        return None
+    if node.val == s.val:
+        return [s]
+    res = dfs(node.left, s)
+    if res:
+        return res + [node]
+    res = dfs(node.right, s)
+    if res: 
+        return res + [node]
+    return None
+
+class Solution:
+    def lowestCommonAncestor(self, root: 'TreeNode', p: 'TreeNode', q: 'TreeNode') -> 'TreeNode':
+        res1 = dfs(root, p)
+        res2 = dfs(root, q)
+
+        lwa = None
+
+        while res1 and res2 and res1[len(res1) - 1] == res2[len(res2) - 1]:
+            lwa = res1.pop()
+            res2.pop()
+
+        return lwa