Is Selection Sort Stable?

Explain why standard Selection Sort is unstable and give a counterexample.

Selection Sort vs Bubble Sort Swaps Count

Why does Selection Sort perform significantly fewer memory writes than Bubble Sort?

Selection Sort on Linked List

Adapt Selection Sort to sort a Singly Linked List in-place.

Searching & Sorting AlgorithmsBeginner LevelStudy Time: 12 mins

Selection Sort Algorithm

Selection Sort divides the input array into a sorted prefix and unsorted suffix, iteratively selecting the minimum value from the unsorted segment and swapping it to the front.

Selection Sort Visualizer

Array loaded. Trigger Selection Sort to view outer/inner loops.

45

[0]

15

[1]

60

[2]

25

[3]

10

[4]

35

[5]

Speed:

Selection Sort Worked Trace

Sample Input:Input Array: [64, 25, 12, 22, 11]

Step 1

Pass 1 - Find Minimum (11)

Scan indices 0..4 to locate minimum element 11 at index 4. Swap arr[0] (64) with arr[4] (11).

[64, 25, 12, 22, 11] -> Min=11 -> Swap -> [11, 25, 12, 22, 64]

Minimum value 11 is placed in its final sorted position at index 0.

Step 2

Pass 2 - Find Next Minimum (12)

Scan unsorted suffix indices 1..4. Minimum is 12 at index 2. Swap arr[1] (25) with arr[2] (12).

[11, 25, 12, 22, 64] -> Min=12 -> Swap -> [11, 12, 25, 22, 64]

Sorted prefix expands to [11, 12].

Step 3

Pass 3 - Swap 22 and 25

Scan unsorted suffix indices 2..4. Minimum is 22 at index 3. Swap arr[2] (25) with arr[3] (22).

Final Output: [11, 12, 22, 25, 64]

Array is completely sorted in O(N²) time using minimal swaps.

Real-world analogy: Sorting Playing Cards

Min Index

Hover over items for details

Scan your hand for the smallest card and place it first. Then scan the rest for the next smallest and place it second.

Min Index= Tracks index of the smallest element in the remaining slice.

Complexity analysis

Scenario Simulator: Dataset Size (N = 500)

Presets:

N = 10N = 10,000

Complexity Curve MapSelection Sort: O(N²) Quadratic Time

Hover curves to inspect classes

Time Steps (N=500)

250,000 steps (Quadratic)

O(N²) Quadratic Time

Space Footprint

O(1) In-Place Space

Memory growth rate as N expands.

Performance Rank

Heavy Tier

Relative efficiency rating for large N.

Operation	Time Complexity	Space Complexity
Best / Worst Case	O(N²)	O(1)

Code implementations

function selectionSort(arr) {
  const n = arr.length;
  for (let i = 0; i < n; i++) {
    let minIdx = i;
    for (let j = i + 1; j < n; j++) {
      if (arr[j] < arr[minIdx]) minIdx = j;
    }
    [arr[i], arr[minIdx]] = [arr[minIdx], arr[i]];
  }
  return arr;
}