#if __INCLUDE_LEVEL__ == 0 #include __BASE_FILE__ namespace { void solve() { int n; cin >> n; int ans = n; for (int d = 1; d * d <= n; ++d) { if (n % d == 0) { --ans; ans -= d * d < n; } } print(ans); } } // namespace int main() { ios::sync_with_stdio(false); cin.tie(nullptr); solve(); } #else // __INCLUDE_LEVEL__ #include using namespace std; template bool chmin(T& x, U&& y) { return y < x && (x = forward(y), true); } template bool chmax(T& x, U&& y) { return x < y && (x = forward(y), true); } namespace std { template istream& operator>>(istream& is, pair& p) { return is >> p.first >> p.second; } template istream& operator>>(istream& is, tuple& t) { return apply([&is](auto&... xs) -> istream& { return (is >> ... >> xs); }, t); } template istream& operator>>(istream& is, tuple&& t) { return is >> t; } template >* = nullptr> auto operator>>(istream& is, R&& r) -> decltype(is >> *begin(r)) { for (auto&& e : r) { is >> e; } return is; } template ostream& operator<<(ostream& os, const pair& p) { return os << p.first << ' ' << p.second; } template ostream& operator<<(ostream& os, const tuple& t) { auto f = [&os](const auto&... xs) -> ostream& { [[maybe_unused]] auto sep = ""; ((os << exchange(sep, " ") << xs), ...); return os; }; return apply(f, t); } template >* = nullptr> auto operator<<(ostream& os, R&& r) -> decltype(os << *begin(r)) { auto sep = ""; for (auto&& e : r) { os << exchange(sep, " ") << e; } return os; } } // namespace std template void print(Ts&&... xs) { cout << tie(xs...) << '\n'; } inline auto rep(int l, int r) { return views::iota(min(l, r), r); } inline auto rep(int n) { return rep(0, n); } inline auto rep1(int l, int r) { return rep(l, r + 1); } inline auto rep1(int n) { return rep(1, n + 1); } inline auto per(int l, int r) { return rep(l, r) | views::reverse; } inline auto per(int n) { return per(0, n); } inline auto per1(int l, int r) { return per(l, r + 1); } inline auto per1(int n) { return per(1, n + 1); } inline auto len = ranges::ssize; #endif // __INCLUDE_LEVEL__