// template {{{ #include using namespace std; // #define int long long #define GET_MACRO(a, b, c, d, NAME, ...) NAME #define REP2(i, n) REP3(i, 0, n) #define REP3(i, a, b) REP4(i, a, b, 1) #define REP4(i, a, b, s) for (int i = (a); i < (int)(b); i += s) #define RREP2(i, n) RREP3(i, 0, n) #define RREP3(i, a, b) for (int i = (b) - 1; i >= (int)(a); i--) #define rep(...) GET_MACRO(__VA_ARGS__, REP4, REP3, REP2)(__VA_ARGS__) #define rrep(...) GET_MACRO(__VA_ARGS__,, RREP3, RREP2)(__VA_ARGS__) #define eb emplace_back #define ef emplace_front #define pb pop_back #define pf pop_front #define all(c) std::begin(c), std::end(c) #define fi first #define se second #define popcnt __builtin_popcountll using uint = unsigned; using ll = long long; using ull = unsigned long long; using ld = long double; using vi = std::vector; using vvi = std::vector; template using maxpq = std::priority_queue, std::less>; template using minpq = std::priority_queue, std::greater>; const int INF = 1e9 + 10; const ll LLINF = 1e18 + 10; const int dx[] = {-1, 0, 1, 0}; const int dy[] = {0, -1, 0, 1}; const int dx8[] = {-1, -1, 0, 1, 1, 1, 0, -1}; const int dy8[] = {0, -1, -1, -1, 0, 1, 1, 1}; template inline T sq(T x){ return x * x; } template inline bool chmax(T &x, U y){ if (x >= y) return false; x = y; return true; } template inline bool chmin(T &x, U y){ if (x <= y) return false; x = y; return true; } template inline T& sort(T &c){ sort(all(c)); return c; } template inline T& reverse(T &c){ reverse(all(c)); return c; } template inline T& rsort(T &c){ sort(all(c), greater()); return c; } template inline T& unique(T &c){ sort(all(c)); c.erase(unique(all(c)), end(c)); return c; } // }}} int main() { ll n; cin >> n; cout << (n / 3 + n / 5) * 2 << endl; }