#include <iostream>
#include <set>
#include <map>
#include <vector>
#include <algorithm>
#include <iomanip>
#include <climits>
#include <numeric>
#include <cmath>
#include <queue>
#include <sstream>
#include <string.h>
#include <bitset>
#include <stack>

using namespace std;
typedef long long ll;

int main(){
  ll N;
  cin >> N;
  
  ll c = N / 15;
  ll a = N / 3 - c;
  ll b = N / 5 - c;
  
  cout << (a + b) * 2 + c * 4 << endl;
  return 0;
}