using System;

public class Program

{

    public static void Main()

    {

        int lineMaxNp = 10000;

        Console.WriteLine("Before v1.39.4");

        for(int np = 9899; np <= 9901; np++) {

            float npDisplay = (float)np / (float)lineMaxNp * 100.0f;

            Console.Write("{0:0.00}%: ", npDisplay);

            if((float)lineMaxNp * 0.99f <= (float)np) {

                Console.WriteLine("up to 100%");

            } else {

                Console.WriteLine("keep");

            }

        }

        Console.WriteLine("");      

        Console.WriteLine("Since v1.40.0");

        for(int np = 9899; np <= 9901; np++) {

            float npDisplay = (float)np / (float)lineMaxNp * 100.0f;

            Console.Write("{0:0.00}%: ", npDisplay);

            if((double)lineMaxNp * 0.99 <= (double)np) {

                Console.WriteLine("up to 100%");

            } else {

                Console.WriteLine("keep");

            }

        }

​

        Console.WriteLine("");      

        Console.WriteLine("Wrong in old version:");

        Console.WriteLine("C# will convert float to double for this operation, ");

        Console.WriteLine("and the left part will be {0}", (double)((float)lineMaxNp * 0.99f));

        Console.WriteLine("");      

        Console.WriteLine("See also: https://stackoverflow.com/questions/2342396/why-does-this-floating-point-calculation-give-different-results-on-different-mac");

​

    }

}