public static int PrintNextBigNumber(int n)
    {
        int size = 0;
        int n2 = n;

        Console.WriteLine("******************************************");
        Console.WriteLine("Nr este {0}",n);

        while (n2 != 0)
        {
            size++;
            n2 /= 10;
        }

        n2 = n;

        int[] array = new int[size];
        for (int i = 0; i < size; ++i)
        {
            array[i] = n2 % 10;
            n2 /= 10;
        }
        Console.WriteLine("Sirul este: " );
        foreach (int a in array)
            Console.Write(a);
        Console.WriteLine();
        for (int i = 0; i < size; ++i)
            for (int j = 0; j < size; ++j)
                if (array[i] > array[j])
                {
                    array[i] += array[j];
                    array[j] = array[i] - array[j];
                    array[i] = array[i] - array[j];
                }

        Console.WriteLine("Sirul sortat cu if (array[i] > array[j]) este: ");
        foreach (int a in array)
            Console.Write(a);
        Console.WriteLine();
        Console.WriteLine("******************************************");

        n2 = 0;

        foreach (int a in array)
        {
            if (a != 0)
                n2 *= 10;
            n2 += a;
        }

        if (n2 == n)
        {
            Console.WriteLine("-1");
            return -1;
        }
        else
        {
            Console.WriteLine(n2);
            return n2;
        }
    }