using System;

public class Program

{

    public static void Main()

    {

        double squaredSum = 0;

        for(int b = 1; b<=100; b++)

            squaredSum+=Math.Pow(b,2);

        double sumSquared = 0;

        for(int a = 1; a<=100; a++)

            sumSquared+=a;

        sumSquared= Math.Pow(sumSquared,2);

        Console.WriteLine(Math.Abs(squaredSum-sumSquared));

    }

}