#include #include #include #include #include template inline bool chmin(T &lhs, const U &rhs) { if (lhs > rhs) { lhs = rhs; return true; } return false; } template inline bool chmax(T &lhs, const U &rhs) { if (lhs < rhs) { lhs = rhs; return true; } return false; } // [l, r) from l to r struct range { struct itr { int i; constexpr itr(int i_): i(i_) { } constexpr void operator ++ () { ++i; } constexpr int operator * () const { return i; } constexpr bool operator != (itr x) const { return i != x.i; } }; const itr l, r; constexpr range(int l_, int r_): l(l_), r(std::max(l_, r_)) { } constexpr itr begin() const { return l; } constexpr itr end() const { return r; } }; // [l, r) from r to l struct revrange { struct itr { int i; constexpr itr(int i_): i(i_) { } constexpr void operator ++ () { --i; } constexpr int operator * () const { return i; } constexpr bool operator != (itr x) const { return i != x.i; } }; const itr l, r; constexpr revrange(int l_, int r_): l(l_ - 1), r(std::max(l_, r_) - 1) { } constexpr itr begin() const { return r; } constexpr itr end() const { return l; } }; constexpr int64_t pr[10] = { 100003, 100019, 100043, 100049, 100057, 100069, 100103, 100109, 100129, 100151 }; int main() { std::vector vec; vec.push_back(1); for (int i = 0; i < 10; ++i) { for (int j = 0; j <= i; ++j) { vec.push_back(pr[i] * pr[j]); } } std::sort(vec.begin(), vec.end()); int N; std::cin >> N; std::cout << vec[N - 1] << '\n'; return 0; }