working solution

[avcode3]

No description provided.

[super30admin]

Your solution for problem1.py is correct and efficient. You have correctly implemented the DFS traversal with backtracking. The code is clean and easy to understand. Well done!

One minor point: In the helper function, you check if root.left is None and root.right is None to identify a leaf node. This is correct. However, you can also write it as if not root.left and not root.right which is more concise but equally clear.

Also, note that the reference solution uses a parameter currNum to pass the current sum, while you use curr_sum. Both are fine. Your solution uses a mutable list for the path, which is modified in place and backtracked by popping. This is efficient and avoids copying the entire path at each node (only copies when a valid path is found).

Overall, excellent job!