Completed s30 Binary-Search-2

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Find First and Last Position of Element in Sorted Array (findpeakeleindex.py)

Strengths:

• The binary search implementation is correct and well-structured
• Uses proper variable naming (left, right, mid)
• Includes time and space complexity comments
• Handles edge cases properly (single element would return 0)

Areas for Improvement:

• This solution solves the wrong problem entirely. The submitted code is for "Find Peak Element" not "Find First and Last Position of Element in Sorted Array"
• For the actual problem, you need to implement two separate binary searches: one to find the first occurrence and one to find the last occurrence of the target
• The solution should return a vector with two values [firstPosition, lastPosition] instead of a single index
• Consider reviewing the problem statement carefully before selecting which problem to solve

For the actual problem, the approach should be:

1. Use binary search to find the leftmost (first) position where target appears
2. Use binary search to find the rightmost (last) position where target appears
3. Return [-1, -1] if target is not found

VERDICT: NEEDS_IMPROVEMENT

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Find Minimum in Rotated Sorted Array (firstandlastposinsortedarr.py)

• Strengths: The solution shows good understanding of binary search for range finding, with proper handling of left/right bias, clean code structure, and correct time/space complexity for its target problem.
• Major Issue: This is the wrong problem entirely. The solution should find the minimum element in a rotated sorted array, not search for a target's range.
• Missing: No attempt to identify the pivot point or minimum element using the rotated array properties.

VERDICT: NEEDS_IMPROVEMENT

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Find Peak Element (mininrotsortedarr.py)

Strengths:

• The code is clean and well-structured
• Comments are present explaining the logic
• Time and space complexity are documented
• Handles edge cases (duplicates) appropriately for its intended problem

Areas for Improvement:

• The student has submitted code for an entirely different problem
• The filename and problem solved don't match the "Find Peak Element" problem
• The solution doesn't check if an element is greater than both neighbors (the core requirement of peak element)
• No binary search logic for finding peaks (comparing with both left and right neighbors)

What was needed:

• A function named findPeakElement (not findMin)
• Logic to check if nums[mid] > nums[mid-1] AND nums[mid] > nums[mid+1]
• Binary search that moves toward the ascending slope to find a peak

VERDICT: NEEDS_IMPROVEMENT