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Lesson 17: Analyzing Bubble Sort Efficiency

Algorithms: From Zero to Hero (A Beginner's Guide)

17. Analyzing Bubble Sort Efficiency

As we saw, Bubble Sort uses nested loops, which typically indicates quadratic time complexity.

Time Complexity Analysis

  • Worst Case: O(N²)
    • Occurs when the array is sorted in reverse order. The inner loop must perform maximum comparisons in every pass.
  • Best Case: O(N)
    • Occurs if the array is already sorted. If we add a flag to detect if any swaps occurred in a pass, we can stop early after the first O(N) pass, achieving linear time.
  • Average Case: O(N²)

Space Complexity

  • Space Complexity: O(1) auxiliary space.
    • Bubble sort is an in-place sorting algorithm, meaning it only requires a minimal, constant amount of extra memory (usually just for temporary variables used in the swap).