int max_of_four(int a, int b, int c, int d)
{

    int aux = 0;

    int arr[4] = {a, b, c, d};

    for (int i = 0; i <= 4; i++)
    {
        if (arr[i] > aux)
        {
            aux = arr[i];
        }
    }

    return aux;
}