Example: Insertion Sort in Array in C++

// Insertion Sort in Array
#include <iostream>
#include <vector> // Using vector for dynamic array, but works with C-style arrays too

// Function to perform insertion sort on an array
void insertionSort(int arr[], int n) {
    // Start from the second element as the first element is considered sorted
    for (int i = 1; i < n; ++i) {
        int key = arr[i]; // The element to be inserted
        int j = i - 1;    // Index of the last element in the sorted part

        // 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]; // Shift element to the right
            j = j - 1;           // Move to the previous element in the sorted part
        }
        arr[j + 1] = key; // Place the key in its correct position
    }
}

// Function to print the array
void printArray(int arr[], int n) {
    for (int i = 0; i < n; ++i) {
        std::cout << arr[i] << " ";
    }
    std::cout << std::endl;
}

int main() {
    // Step 1: Define an array to be sorted
    int arr[] = {12, 11, 13, 5, 6};
    int n = sizeof(arr) / sizeof(arr[0]);

    std::cout << "Original array: ";
    printArray(arr, n);

    // Step 2: Apply insertion sort
    insertionSort(arr, n);

    std::cout << "Sorted array: ";
    printArray(arr, n);

    return 0;
}