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Design HashSet (Exercise_1.py)

Strengths:

1. Your solution correctly implements the double hashing technique, matching the reference solution's approach.
2. You properly identified and handled the edge case for the value 1,000,000 by allocating an extra slot at index 0.
3. The lazy allocation of secondary arrays is a great optimization that saves memory.
4. Your code is well-structured with clear helper methods.

Areas for Improvement:

1. Comments: The extensive comments at the top of the file, while showing your thought process, are too verbose for production code. Consider condensing them into a brief explanation of the approach. Also, avoid self-deprecating language like "No you doofus" - keep comments professional.
2. Unused variable: self.max_value = 1000000 is declared but never used. You can remove it.
3. Documentation: Consider adding a brief docstring to each method explaining its purpose and complexity.
4. Type hints: Good use of type hints in add, but consider adding return type hints to remove and contains for consistency.

VERDICT: PASS

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Min Stack (Exercise_2.py)

Your solution is creative and well-thought-out! The approach of storing a reference to the last known minimum in each node is elegant and achieves the same O(1) time complexity as the reference solution's two-stack approach. Here are some observations:

Strengths:

1. Excellent documentation: Your comments and docstring clearly explain the conceptual approach, edge cases, and constraints analysis. This is a great practice.
2. Correct logic: The solution correctly handles all operations, including the tricky case of popping the minimum element.
3. Clean code structure: Using a dataclass for the Node is a nice Pythonic touch.
4. O(1) time complexity: All operations meet the required time complexity.

Areas for Improvement:

1. Type hints: Consider using Optional[Node] for fields that can be None:

   from typing import Optional
   
   @dataclass
   class Node:
       value: int
       last_known_lowest_element: Optional['Node'] = None

2. Method naming: The problem uses val as the parameter name. While value is more descriptive, matching the problem's interface can be helpful for clarity.
3. Alternative approach: The reference solution uses two stacks (one for values, one for minimums). Your approach is essentially equivalent but uses a linked-list-like structure. Both are valid solutions.

Overall, this is a high-quality solution that demonstrates strong problem-solving skills and good coding practices. Keep up the great work!

VERDICT: PASS