Completed Design-1 problems

[shaurya22c]

No description provided.

[super30admin]

Design HashSet (design_hashset.py)

Strengths:

1. Correct implementation of all required operations
2. Good use of dummy nodes to simplify edge cases in linked list operations
3. Well-documented code with clear comments
4. Includes a helpful display method for debugging
5. Proper handling of duplicate additions (no duplicates in set)

Areas for Improvement:

1. Memory Efficiency: Pre-allocating 10^4 dummy nodes wastes memory. Consider lazy allocation where buckets are only created when needed.
2. Worst-Case Complexity: The chaining approach has O(n) worst-case complexity. Consider using double hashing (like the reference solution) for true O(1) operations.
3. Hash Function: Using a simple modulo with a fixed size of 10^4 can lead to many collisions. Consider using a larger array or a better hash function.
4. Space Optimization: The reference solution uses a 2D boolean array which is more space-efficient than linked lists for this use case.

VERDICT: PASS

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Min Stack (min_stack.py)

Strengths:

1. Your solution correctly implements the MinStack with O(1) time complexity for all operations
2. Good use of docstrings to explain the approach and complexity
3. Clean, readable code with proper type hints
4. The two-stack approach is correctly implemented
5. Including a main() function to demonstrate the solution is a nice touch

Areas for Improvement:

1. The return statement in the push method after appending to minstack is unnecessary - you can remove it for cleaner code
2. Consider adding more test cases to your main() function to cover edge cases (e.g., empty stack operations, single element stack, duplicate minimum values)
3. You could add input validation or assertions to ensure the stack is non-empty before pop/top/getMin operations (though the problem guarantees this)
4. Consider using self.minstack[-1] directly in getMin without the intermediate min_val variable in push for slightly cleaner code

VERDICT: PASS