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Quick Sort Using Hoare's Partition

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Quick Sort Using Hoare's Partition

Don’t start Quick Sort Using Hoare's Partition with jargon. Start with names A→Z. That is the whole point.

Quick Sort Using Hoare's Partition on the board: n log n vs n². Then say what names A→Z looks like after.

Quick Sort Using Hoare's Partition exists so Riya can keep names A→Z correct in the roll list.

Use Quick Sort Using Hoare's Partition when names A→Z must stay clear. If a simpler DSA step works, use that instead.

Quick Sort Using Hoare's Partition miss: unstable sort when equal keys matter. Fix it before you talk about advanced DSA.

After Quick Sort Using Hoare's Partition, Riya should still remember unstable sort when equal keys matter.

Viva for Quick Sort Using Hoare's Partition: what it is → n log n vs n² → the mistake (unstable sort when equal keys matter).

Exam tip

For Quick Sort Using Hoare's Partition: 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 Using Hoare's Partition — quick sort partitions around a pivot, then sorts both sides.

Short notes

DefQuick Sort Using Hoare's Partition — Riya uses it for names A→Z in the roll list.
RuleQuick Sort Using Hoare's Partition → n log n vs n².
RememberQuick Sort Using Hoare's Partition + time vs memory (the roll list).
UseQuick Sort Using Hoare's Partition in the roll list (names A→Z).
TrapQuick Sort Using Hoare's Partition — unstable sort when equal keys matter.
ExQuick Sort Using Hoare's Partition → 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 Using Hoare's Partition

Example

Short notes

Questions

Quick Sort Using Hoare's Partition

Example

Short notes

Questions