Problem:
Score : 200 points

Problem Statement

Let us define the FizzBuzz sequence a_1,a_2,... as follows:

If both 3 and 5 divides i, a_i=\mbox{FizzBuzz}.

If the above does not hold but 3 divides i, a_i=\mbox{Fizz}.

If none of the above holds but 5 divides i, a_i=\mbox{Buzz}.

If none of the above holds, a_i=i.

Find the sum of all numbers among the first N terms of the FizzBuzz sequence.

Constraints

1 \leq N \leq 10^6

Input

Input is given from Standard Input in the following format:

N

Output

Print the sum of all numbers among the first N terms of the FizzBuzz sequence.

Sample Input 1

15

Sample Output 1

60

The first 15 terms of the FizzBuzz sequence are:

1,2,\mbox{Fizz},4,\mbox{Buzz},\mbox{Fizz},7,8,\mbox{Fizz},\mbox{Buzz},11,\mbox{Fizz},13,14,\mbox{FizzBuzz}

Among them, numbers are 1,2,4,7,8,11,13,14, and the sum of them is 60.

Sample Input 2

1000000

Sample Output 2

266666333332

Watch out for overflow.

Solution in C# (Mono-mcs 6.8.0.105) (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using static System.Console;
using static System.Math;

namespace Atcoder
{
    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                Solve.Answer();
            }
            catch (Exception ex)
            {
                WriteLine(ex.ToString());
            }
        }
    }

    static class Solve
    {
        public static void Answer()
        {
            var N = IO_ShortCut.ReadInt;
            long ans = 0;
            for (int i = 1; i <= N; i++)
            {
                if (i % 3 == 0 || i % 5 == 0)
                    continue;

                ans += i;
            }
            WriteLine(ans);
        }
    }

    static class IO_ShortCut
    {
        #region Input
        public static string ReadString => ReadLine();
        public static int ReadInt => int.Parse(ReadLine());
        public static long ReadLong => long.Parse(ReadLine());
        public static double ReadDouble => double.Parse(ReadLine());

        public static List<string> ReadSplitString => ReadLine().Split().ToList();
        public static List<int> ReadSplitInt => ReadLine().Split().Select(s => int.Parse(s)).ToList();
        public static List<long> ReadSplitLong => ReadLine().Split().Select(s => long.Parse(s)).ToList();
        public static List<double> ReadSplitdouble => ReadLine().Split().Select(s => double.Parse(s)).ToList();
        #endregion

        #region Output
        public static void OutJoinSpace<T>(IEnumerable<T> list) => WriteLine(string.Join(" ", list));
        #endregion
    }
}