#include <bits/stdc++.h> using namespace std; #define rep(i,n) for(int i=0;i<n;++i) #define Rep(i,n) for(int i=1;i<=n;++i) #define rrep(i,n) for(int i=n-1;0<=i;--i) #define rRep(i,n) for(int i=n;0<i;--i) #define range(i,a,b) for(int i=(a);i<(b);++i) #define mp make_pair #define pb push_back #define all(x) x.begin(), x.end() #define EPS 1e-8 #define INF 1e8 typedef double Real; typedef int Int; typedef vector<Int> vi; typedef vector<vector<Int> > vvi; typedef pair<Int,Int> pii; const vi dy = {-1, 0, 1, 0}, dx = {0, -1, 0, 1}; template <typename K, typename V> ostream& operator<< (ostream& out, const pair<K, V>& p) { out << '(' << p.first << ", " << p.second << ')'; return out; } template <typename T> ostream& operator<< (ostream& out, const vector<T>& v) { out << '['; rep(i, v.size()) out << v[i] << ","; out << "\b], " << v.size(); return out; } void solve(){ unsigned long N; cin >> N; cout << (N/3+N/5)*2 << endl; } signed main() { cin.tie(0); ios::sync_with_stdio(false); cout << fixed << setprecision(9); solve(); return 0; }