#include <iostream>
#include <math.h>
#include <algorithm>
#include <functional>
#include <vector>
#include <typeinfo>
#include <climits>
#include <ctype.h>
#include <string>
#include <stack>
using namespace std;
#define FOR(i, a, n) for (int i = a; i < n; i++)
#define REP(i, n) for(int i = 0; i < n; i++)
struct cww{cww(){ios::sync_with_stdio(false);cin.tie(0);}}star;

int main(){
    int n;
    cin >> n;

    int cnt = 0;
    FOR(i, 1, n + 1){
        if(i % 3 == 0 and i % 5 == 0) cnt += 4;
        else if(i % 3 == 0 and i % 5 != 0) cnt += 2;
        else if(i % 3 != 0 and i % 5 == 0) cnt += 2;   
    }
    cout << cnt << endl;


    return 0;
}