using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

        TestInput("2");

        TestInput("2.5");

        TestInput("2.49");

        TestInput("2.000000000000");

        TestInput("2.0000000000001");

    }

    static void TestInput(string text)

    {

        double a, b;

        a = Convert.ToDouble(text);

        b = Convert.ToInt32(a);

        if(a == b)

            Console.WriteLine("input {0} is an integer", text);

        else

            Console.WriteLine("input {0} is not an integer", text);

    }

}