Done Array 2

[Nav0708]

No description provided.

[super30admin]

Disappeared Numbers (Problem-1.py)

Strengths:

• Excellent solution that meets the follow-up requirement (O(n) time, O(1) space)
• Well-commented code that explains the algorithm clearly
• Correctly handles the edge case where a value might already be negative
• Clean and readable implementation

Areas for Improvement:

• The three-line explanation in comments is good, but could be more structured
• Consider adding a brief docstring at the class level explaining the problem
• The code could benefit from a small comment explaining why we use O(1) space despite having a result array (since the problem states the returned list doesn't count as extra space)

This is a solid, optimal solution that demonstrates understanding of the in-place marking technique commonly used for this classic problem.

VERDICT: PASS

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max and min (Problem-2.py)

The student has submitted a solution for the wrong problem entirely. The "max and min" problem requires finding the minimum and maximum values in an array using fewer than 2*(N-2) comparisons, which the reference solution addresses by comparing elements in pairs. The submitted solution solves the Game of Life problem, which is completely unrelated.

Strengths of the submitted solution (Game of Life):

• Good use of direction vectors for neighbor traversal
• Correct in-place modification strategy using marker values (-1 for dying, 2 for becoming alive)
• Clear comments explaining the approach
• Proper boundary checking

Areas for improvement:

• The solution must address the actual problem being asked
• For the min/max problem, the student should implement a pairwise comparison approach that processes two elements at a time, comparing them with each other first, then comparing the smaller with min and larger with max

VERDICT: NEEDS_IMPROVEMENT

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Life Game

Strengths:

• Correctly implements the in-place algorithm using marker values (-1 for dying, 2 for becoming alive)
• Good use of abs() to detect original live state even after marking
• Proper boundary checking for neighbor validation
• Well-commented code that explains the algorithm clearly
• Matches the reference solution's approach and complexity

Areas for Improvement:

• The second pass could be slightly more efficient by using direct comparison instead of >0 check, but current implementation is correct
• Consider renaming 'dir' to 'direction' or 'd' for better readability
• The comment header mentions "we only increment live cells when we explore all the neighbors for live cells and update it" which is slightly confusing

Overall, this is a solid implementation that correctly solves the problem with optimal time and space complexity.

VERDICT: PASS