using System;

public class Program

{

    public static void Main()

    {

        int number = 1;

        float divisable;

        const int three = 3;

        const int five = 5;

        int NumSum = 0;

        while (number <= 1000)

        {

        divisable = number % three;

        if (divisable == 0)

            {

            //Console.WriteLine(number);

            NumSum = NumSum + number;

            }

            divisable = number % five;

        if (divisable == 0)

            {

            //Console.WriteLine(number);

            NumSum = NumSum + number;

            }

            number = number + 1;

        }

        Console.WriteLine(NumSum);

    }

}