How to merge two arrays in C++

In this article, we will see how you can merge two arrays in C++. The array is a collection of similar types of data items in a larger group. The array is used to store multiple similar types of values in a single variable.

Code:

In the below code, we will see how we can merge two arrays into a large single array in C++.

int main()
{
    int arr1[] = { 4, 2, 3 };
    int arr2[] = { 7, 8, 6 };

    //Finding the aray length
    int n1 = sizeof(arr1) / sizeof(arr1[0]);
    int n2 = sizeof(arr2) / sizeof(arr2[0]);

    // Creating new array by merging two arrays n1 & n2
    int arr3[n1 + n2];

    // Copy the elements from the first array
    for (int i = 0; i < n1; i++)
        arr3[i] = arr1[i];

    // Copy the elements from the second array
    for (int i = 0; i < n2; i++)
        arr3[n1 + i] = arr2[i];

    // Print the concatenated array
    cout << "Merged Array: ";
    for (int i = 0; i < n1 + n2; i++)
        cout << arr3[i] << " ";
    cout << endl;

    return 0;
}

Output:

Merged Array: 4 2 3 7 8 6

Time Complexity: O(N+M), where N and M are the lengths of both arrays.
Auxiliary Space: O(N+M)