using System;

public class Program

{

    public static void Main()

    {

        int i,n,p=0;

        Console.WriteLine("enter you value");

        n=Convert.ToInt32(Console.ReadLine());

        for(i=n;i>=0;i--)

        {

            if(i%3==0 || i%5==0)

            {

             p=p+i;

            }

        }

        Console.WriteLine("{0}",p);

    }

}