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Quick Sort vs Merge Sort

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Quick Sort vs Merge Sort

Quick Sort vs Merge Sort is a DSA idea you prove with names A→Z, not with a slogan.

Do Quick Sort vs Merge Sort once by hand. n log n vs n². Change one input. Say the new result out loud.

Without Quick Sort vs Merge Sort, the roll list gets messy and names A→Z is hard to trust.

Use Quick Sort vs Merge Sort when names A→Z must stay clear. If a simpler DSA step works, use that instead.

Quick Sort vs Merge Sort miss — unstable sort when equal keys matter. Fix it before you talk about advanced DSA.

After Quick Sort vs Merge Sort, Kabir should still remember unstable sort when equal keys matter.

One breath for Quick Sort vs Merge Sort, then names A→Z, then unstable sort when equal keys matter. Sit down.

Exam tip

For Quick Sort vs Merge Sort: definition + the roll list + one failure.

Example

def quick_sort(arr):
    if len(arr) <= 1:
        return arr
    pivot = arr[len(arr) // 2]
    left = [x for x in arr if x < pivot]
    mid = [x for x in arr if x == pivot]
    right = [x for x in arr if x > pivot]
    return quick_sort(left) + mid + quick_sort(right)

print(quick_sort([5, 1, 4, 2, 3]))

Quick Sort vs Merge Sort — quick sort partitions around a pivot, then sorts both sides.

Short notes

DefQuick Sort vs Merge Sort — Kabir uses it for names A→Z in the roll list.
RuleQuick Sort vs Merge Sort → n log n vs n².
RememberQuick Sort vs Merge Sort + a dry-run table (the roll list).
UseQuick Sort vs Merge Sort in the roll list (names A→Z).
TrapQuick Sort vs Merge Sort — unstable sort when equal keys matter.
ExQuick Sort vs Merge Sort → names A→Z.

def quick_sort(arr): if len(arr) <= 1: return arr pivot = arr[len(arr) // 2] left = [x for x in arr if x < pivot] mid = [x for x in arr if x == pivot] right = [x for x in arr if x > pivot] return quick_sort(left) + mid + quick_sort(right) print(quick_sort([5, 1, 4, 2, 3]))

Quick Sort vs Merge Sort

Example

Short notes

Questions

Quick Sort vs Merge Sort

Example

Short notes

Questions