Design-2 Completed

[lakshmidurgat]

No description provided.

[super30admin]

Implement Queue using Stacks (QueueImpleWithStack.java)

Strengths:

• Your solution is correct and uses the optimal two-stack approach
• The code is clean, well-organized, and easy to understand
• Good documentation with comments explaining the approach and complexity
• The logic for transferring elements between stacks is correctly implemented

Areas for Improvement:

• Consider using Deque<Integer> (specifically ArrayDeque) instead of Stack<Integer>. In Java, Stack is a legacy class that extends Vector, which is synchronized and has performance overhead. ArrayDeque is the recommended replacement for stack-like behavior.
• The peek() method could be slightly optimized by calling it from pop() to avoid code duplication (as shown in the reference solution), but your current approach is also valid and arguably more readable.
• Minor: You could add input validation or handle edge cases more explicitly, though the problem guarantees valid calls.

Overall, this is a solid solution that demonstrates a clear understanding of the problem and the optimal approach.

VERDICT: PASS

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Design HashMap (HashMap.java)

Strengths:

• Clean, well-organized implementation that correctly handles all edge cases.
• Good use of the dummy head node pattern to simplify linked list operations.
• Proper handling of the "key not found" case in all three operations.
• The remove implementation is concise and correct.

Areas for Improvement:

• Encapsulation: The helper methods getHash and getPrev should be declared as private rather than public. They are internal implementation details and shouldn't be part of the public API.
• Comments: Adding brief comments explaining the dummy head pattern would improve code clarity for future readers.
• Bucket size consideration: While 1000 buckets works for the given constraints, in a real-world scenario, you'd want

VERDICT: NEEDS_IMPROVEMENT