static unsafe void Main(string[] args)
        {
            int[] mang1 = new int[5];
            int i;
            for (i = 0; i < 5; i++)
            {
                Console.WriteLine("Nhap gia tri [{0}] cua mang a ", i);
                mang1[i] = int.Parse(Console.ReadLine());
            }
            int[] mang2 = new int[5];
            for (i = 0; i < 5; i++)
            {
                Console.WriteLine("Nhap gia tri [{0}] cua mang b", i);
                mang2[i] = int.Parse(Console.ReadLine());
            }
            Console.Write("Mang a ban da nhap:");
            for (i = 0; i < 5; i++)
            {
                Console.Write(" " + mang1[i]);
            }
            Console.Write("\nMang b ban da nhap:");
            for (i = 0; i < 5; i++)
            {
                Console.Write(" " + mang2[i]);
            }
            int[] mang3 = new int[5];
            Console.Write("\nMang c ban da nhap:");
            fixed (int* ptr = mang3)
                for (i = 0; i < 5; i++)
                {
                    mang3[i] = mang1[i] + mang2[i];
                    Console.WriteLine("Dia chi cua mang3[{0}]={1}", i, (int)(ptr + i));
                    Console.WriteLine("Gia tri cua mang3[{0}]={1}", i, *(ptr + i));
                }
            Console.ReadKey();
        }
    }
}