Array Sorting

Bubble sort visualization — largest element bubbles to end each pass; O(n²) time O(1) space

Bubble Sort

Repeatedly compare adjacent elements and swap if they're in the wrong order. Simple but O(n²) — not for large datasets.

c

#include <stdio.h>
void bubbleSort(int arr[], int n) {
    for (int i = 0; i < n-1; i++)
        for (int j = 0; j < n-i-1; j++)
            if (arr[j] > arr[j+1]) {
                int tmp = arr[j];
                arr[j] = arr[j+1];
                arr[j+1] = tmp;
            }
}
int main() {
    int arr[] = {64, 34, 25, 12, 22, 11, 90};
    int n = 7;
    bubbleSort(arr, n);
    for (int i=0;i<n;i++) printf("%d ",arr[i]);
    return 0;
}

Output

11 12 22 25 34 64 90

Selection Sort

c

void selectionSort(int arr[], int n) {
    for (int i=0;i<n-1;i++) {
        int minIdx = i;
        for (int j=i+1;j<n;j++)
            if (arr[j] < arr[minIdx]) minIdx = j;
        int tmp = arr[minIdx];
        arr[minIdx] = arr[i];
        arr[i] = tmp;
    }
}

Sorting Algorithm Comparison

Algorithm	Best	Average	Worst	Stable?
Bubble Sort	O(n)	O(n²)	O(n²)	Yes
Selection Sort	O(n²)	O(n²)	O(n²)	No
Insertion Sort	O(n)	O(n²)	O(n²)	Yes
stdlib qsort	O(n log n)	O(n log n)	O(n²)	No

Master the Art of C Programming

Explore Topics