using System;

public class Program

{

    public static void Main()

    {

        int n,count, negative = 0,positive = 0; 

​

            for ( count = 0;count < 20; count = count + 1)

            {

                Console.Write("input a number: ");

                n = Convert.ToInt32(Console.ReadLine());

                if (n > 0)

                {

                    positive = positive + 1;

                }

                else  

                {

                    negative = negative + 1;

                }

            }

            Console.WriteLine("there are " + positive + " positive numbers and " + negative + " negative numbers");

            Console.ReadLine();

    }

}