Example: C++ Insertion Sort Algorithm in C++

// C++ Insertion Sort Algorithm
#include <iostream>

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

// Function to perform insertion sort
void insertionSort(int arr[], int n) {
    // Iterate from the second element (index 1) to the end of the array
    for (int i = 1; i < n; i++) {
        // 'key' is the element to be inserted into the sorted subarray
        int key = arr[i];
        // 'j' is the index of the last element in the sorted subarray
        int j = i - 1;

        // 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 left in the sorted subarray
        }
        // Place 'key' at its correct position in the sorted subarray
        arr[j + 1] = key;
    }
}

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

    // Step 2: Print the original array
    std::cout << "Original array: ";
    printArray(arr, n);

    // Step 3: Apply insertion sort
    insertionSort(arr, n);

    // Step 4: Print the sorted array
    std::cout << "Sorted array:   ";
    printArray(arr, n);

    return 0;
}