FirstTenNumbers2

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;


class FirstTenNumbers
{
    static void Main()
    {
        int[] numbers = new int[20];

        numbers[0] = 2;
        numbers[1] = -3;

        int i;

        for (i = 2; i < numbers.Length; i++)
        {
            if (i % 2 == 0)
            {
                numbers[i] = numbers[i - 2] + 2;
            }
            else
            {
                numbers[i] = numbers[i - 2] - 2;
            }
        }
        for (i = 0; i < 10; i++)
        {
            Console.WriteLine(numbers[i]);
        }
    }
}