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

namespace Root
{
    class Program
    {
        public static bool RationalRoot(int num)
        {
            int sum = 0, n = 1;
            while (sum < num)
            {
                sum += n;
                n += 2;
            }
            return sum==num;
        }
        public static int HaveRootCount()
        {
            int count = 0;
            int input = -1;
            for (int i=0;i<4;i++)
            {
                while (input <= 0) // בדיקת קלט
                {
                    Console.WriteLine("Type a positive number.");
                    input = int.Parse(Console.ReadLine());
                }
                if (RationalRoot(input))
                {
                    count++;
                }
                input = -1;
            }

            return count;
        }
        static void Main(string[] args)
        {
            int count = HaveRootCount();
            Console.WriteLine("{0} of the inputted numbers have a natural number root.",count);
        }
    }
}