Example: Insertion Sort in C

// Insertion Sort
#include <stdio.h>

// Function to print an array
void printArray(int arr[], int size) {
    for (int i = 0; i < size; i++) {
        printf("%d ", arr[i]);
    }
    printf("\n");
}

// Function to perform insertion sort
void insertionSort(int arr[], int n) {
    // Step 1: Iterate from the second element (index 1) to the end of the array
    for (int i = 1; i < n; i++) {
        // Step 2: Store the current element to be inserted
        int key = arr[i];
        // Step 3: Initialize j to the index of the element just before 'key'
        int j = i - 1;

        // Step 4: Move elements of arr[0..i-1], that are greater than key,
        //         to one position ahead of their current position
        while (j >= 0 && arr[j] > key) {
            arr[j + 1] = arr[j];
            j = j - 1;
        }
        // Step 5: Place the key at its correct position in the sorted sub-array
        arr[j + 1] = key;

        printf("Pass %d: ", i);
        printArray(arr, n);
    }
}

int main() {
    int arr[] = {12, 11, 13, 5, 6};
    int n = sizeof(arr) / sizeof(arr[0]);

    printf("Original array: ");
    printArray(arr, n);

    insertionSort(arr, n);

    printf("Sorted array: ");
    printArray(arr, n);

    return 0;
}