Hashing-2: first commit

[sudheerkreddy]

No description provided.

[super30admin]

Subarray Sum Equals K (SubArraySumEqualsK.java)

Strengths:

• Correct algorithm implementation using prefix sum with hashmap
• Clear variable naming and logical structure
• Proper initialization of map with {0: 1}
• Good use of early return with result variable

Areas for Improvement:

• Consolidate the map update logic using getOrDefault() to avoid redundant hash lookups
• Consider using enhanced for-loop (for (int num : nums)) for cleaner code, as shown in the reference

Suggested Optimization:
Replace:

if(map.containsKey(rSum)) {
    map.put(rSum, map.get(rSum)+1);
}
else {
    map.put(rSum, 1);
}

With:

map.put(rSum, map.getOrDefault(rSum, 0) + 1);

VERDICT: PASS

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Contiguous Binary Subarray (ContiguousArray.java)

Strengths:

• Excellent implementation that mirrors the optimal solution approach
• Clean, readable code with good naming conventions
• Correctly handles edge cases (e.g., when the entire array has equal 0s and 1s)
• Well-documented with complexity comments

Areas for Minor Improvement:

• Could use map.getOrDefault(rSum, -1) to slightly reduce code, but current approach is more explicit
• Consider adding a brief comment explaining the algorithm approach for future maintainability

The solution demonstrates a solid understanding of the problem and its optimal solution strategy.

VERDICT: PASS

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Longest Palindrome in a string (LongestPalindrome.java)

Strengths:

• Correct algorithm implementation with clear logic
• Good defensive programming with null/empty checks
• Clean, readable code with meaningful variable names
• Proper use of HashSet for tracking unpaired characters
• Matches reference solution's time complexity

Areas for Improvement:

• The set.contains() check before set.remove() is redundant. You can simply call set.remove(c) which returns true if the element was present, eliminating the need for a separate contains check.
• Consider using enhanced for-loop (for (char c : s.toCharArray())) like the reference solution for slightly cleaner code, though this is minor.

The solution is functionally correct and efficient. These are minor style suggestions that don't affect correctness.

VERDICT: PASS