Completed BS-02

[bansariradadiya01]

No description provided.

[super30admin]

Find the First and Last Position of an Element in given Sorted Array (last_first.java)

• The student needs to actually implement the solution for finding the first and last position of an element in a sorted array.
• The solution should use binary search to achieve O(log n) time complexity as required by the problem.
• Consider implementing two helper functions: one to find the first occurrence and another to find the last occurrence of the target.
• Make sure to handle edge cases such as empty arrays and when the target is not found.

VERDICT: NEEDS_IMPROVEMENT

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Find the Minimum Element in a Rotated Array(sorted) (min_element.java)

Strengths:

• Correctly implements binary search approach
• Good variable naming (low, high, mid)
• Handles the sorted portion check correctly (arr[low] <= arr[high])
• O(1) space complexity achieved

Areas for Improvement:

1. Critical Bug: Change while(low < high) to while(low <= high) to ensure the loop continues until a single element remains
2. Missing closing brace: The class is missing a closing brace }
3. Incomplete minimum check: The condition only checks arr[mid] < arr[mid-1] but should also check arr[mid] < arr[mid+1] to properly identify the minimum element at all positions
4. Code structure: Consider extracting the algorithm into a separate method rather than putting everything in main()
5. Edge case handling: Add checks for boundary conditions when mid is at position 0 or n-1

The solution is close to correct but has a critical loop condition bug that could cause it to fail in certain cases.

VERDICT: NEEDS_IMPROVEMENT

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Find the Peak Element (peak.java)

The student has not submitted any actual code solution. The file appears to be empty (only contains comments showing the filename). To complete this assignment, the student needs to:

1. Implement the findPeakElement method that finds a peak element in O(log n) time complexity using binary search
2. The solution should handle edge cases like:
   • Single element arrays
   • Arrays where the peak is at the beginning or end
   • Arrays with multiple peaks
3. Compare the element at mid with its neighbors to determine which half to search

The reference solution demonstrates the correct approach using binary search with the key insight that if nums[mid+1] > nums[mid], we must search the right half because there must be a peak there.

VERDICT: NEEDS_IMPROVEMENT