C# работа с массивами

using System;

namespace Example
{
    class Program
    {
        const int MAX_N = 128;

        static void add(int k, int x, ref int n, ref int[] a)
        {
            if (k >= 0 && k < n && n < MAX_N)
            {
                for (int i = n; i > k; --i)
                    a[i] = a[i - 1];

                a[k] = x;

                ++n;
            }
        }

        static void erase(int k, ref int n, ref int[] a)
        {
            if (n > 0 && k >= 0 && k < n)
            {
                for (int i = k; i < n - 1; ++i)
                    a[i] = a[i + 1];

                --n;
            }
        }

        static void print(int n, int[] a)
        {
            for (int i = 0; i < n; ++i)
                Console.Write("{0} ", a[i]);

            Console.Write("\n");
        }

        static void Main()
        {
            Console.Write("n = ");
            int n = int.Parse(Console.ReadLine());

            int[] a = new int[MAX_N];

            Random num = new Random();

            for (int i = 0; i < n; ++i)
                a[i] = num.Next(100);

            print(n, a);

            string state = "";

            while (state != "stop")
            {
                state = Console.ReadLine();

                string[] s = state.Split(" ");

                if (s[0] == "add") add(int.Parse(s[1]), int.Parse(s[2]), ref n, ref a);
                else if (s[0] == "erase") erase(int.Parse(s[1]), ref n, ref a);

                print(n, a);
            }

        }
    }
}