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Quick Sort Algorithm

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Quick Sort Algorithm

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

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

Skip Quick Sort Algorithm and unstable sort when equal keys matter shows up in the roll list.

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

Don’t do this with Quick Sort Algorithm — unstable sort when equal keys matter. Interviewers spot it in ten seconds.

Place Quick Sort Algorithm next to nearby DSA work — n log n vs n² is the link.

Viva for Quick Sort Algorithm — what it is → n log n vs n² → the mistake (unstable sort when equal keys matter).

Exam tip

Board: names A→Z. Dry-run Quick Sort Algorithm. Name the trap: unstable sort when equal keys matter.

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 Algorithm — quick sort partitions around a pivot, then sorts both sides.

Short notes

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

Example

Short notes

Questions

Quick Sort Algorithm

Example

Short notes

Questions