public static void insertionSort1(int n, List<int> arr)
{
    var last = arr[n - 1];

    for (int i = n - 1; i >= 0; i--)
    {
        if (i == 0 || last > arr[i - 1])
        {
            arr[i] = last;
            Console.WriteLine(string.Join(" ", arr));
            break;
        }
        else
        {
            arr[i] = arr[i - 1];
            Console.WriteLine(string.Join(" ", arr));
        }
    }
}