#include "bits/stdc++.h"
using namespace std;
using ll = long long;
#define int ll
#define double long double
void YN(bool flg){cout<<(flg?"YES":"NO")<<endl;}
void Yn(bool flg){cout<<(flg?"Yes":"No")<<endl;}
void yn(bool flg){cout<<(flg?"yes":"no")<<endl;}
#define SORT(a) sort(a.begin(),a.end())
#define REVERSE(a) reverse(a.begin(),a.end())
#define REP(i, n) for(int i = 0;i < n;i++)
#define FOR(i, m, n) for(int i = m;i < n;i++)
#define db(n) cout << "### " << n << " ###" << endl;
typedef vector<int> VI;
typedef vector<VI> VVI;
const long long MOD=1000000007;
const long long INF = 10e10;
const double PI = acos(-1.0);
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
int GCD(int a, int b) { return b ? GCD(b, a%b) : a; }
int LCM(int a, int b) { int g = GCD(a, b); return a / g * b; }
//---------------------------------------------------------------------------------------------

signed main(){
    cin.tie(0);
    ios::sync_with_stdio(0);
    cout<<fixed<<setprecision(15);

    int n; cin >> n;
    cout << (n/3+n/5)*2 << endl;

    return 0;
}