#define MOD_TYPE 2 #include using namespace std; #if 0 #pragma GCC target("avx2") #pragma GCC optimize("O3") #pragma GCC optimize("unroll-loops") #endif #if 0 #include #include #include #include using namespace __gnu_pbds; using namespace __gnu_cxx; template using extset = tree, rb_tree_tag, tree_order_statistics_node_update>; #endif #if 0 #include #include using Int = boost::multiprecision::cpp_int; using lld = boost::multiprecision::cpp_dec_float_100; #endif #pragma region Macros using ll = long long int; using ld = long double; using pii = pair; using pll = pair; using pld = pair; template using smaller_queue = priority_queue, greater>; constexpr ll MOD = (MOD_TYPE == 1 ? (ll)(1e9 + 7) : 998244353); constexpr int INF = (int)1e9 + 10; constexpr ll LINF = (ll)4e18; constexpr ld PI = acos(-1.0); constexpr ld EPS = 1e-7; constexpr int Dx[] = {0, 0, -1, 1, -1, 1, -1, 1, 0}; constexpr int Dy[] = {1, -1, 0, 0, -1, -1, 1, 1, 0}; #define REP(i, m, n) for (ll i = m; i < (ll)(n); ++i) #define rep(i, n) REP(i, 0, n) #define REPI(i, m, n) for (int i = m; i < (int)(n); ++i) #define repi(i, n) REPI(i, 0, n) #define MP make_pair #define MT make_tuple #define YES(n) cout << ((n) ? "YES" : "NO") << "\n" #define Yes(n) cout << ((n) ? "Yes" : "No") << "\n" #define possible(n) cout << ((n) ? "possible" : "impossible") << "\n" #define Possible(n) cout << ((n) ? "Possible" : "Impossible") << "\n" #define all(v) v.begin(), v.end() #define NP(v) next_permutation(all(v)) #define dbg(x) cerr << #x << ":" << x << "\n"; #define UNIQUE(v) v.erase(unique(all(v)), v.end()) struct io_init { io_init() { cin.tie(0); ios::sync_with_stdio(false); cout << setprecision(30) << setiosflags(ios::fixed); }; } io_init; template inline bool chmin(T &a, T b) { if (a > b) { a = b; return true; } return false; } template inline bool chmax(T &a, T b) { if (a < b) { a = b; return true; } return false; } inline ll CEIL(ll a, ll b) { return (a + b - 1) / b; } template inline void Fill(A (&array)[N], const T &val) { fill((T *)array, (T *)(array + N), val); } template vector compress(vector &v) { vector val = v; sort(all(val)), val.erase(unique(all(val)), val.end()); for (auto &&vi : v) vi = lower_bound(all(val), vi) - val.begin(); return val; } template constexpr istream &operator>>(istream &is, pair &p) noexcept { is >> p.first >> p.second; return is; } template constexpr ostream &operator<<(ostream &os, pair &p) noexcept { os << p.first << " " << p.second; return os; } template constexpr istream &operator>>(istream &is, vector &v) noexcept { for (int i = 0; i < v.size(); i++) is >> v[i]; return is; } template constexpr ostream &operator<<(ostream &os, vector &v) noexcept { for (int i = 0; i < v.size(); i++) os << v[i] << (i + 1 == v.size() ? "" : " "); return os; } template constexpr void operator--(vector &v, int) noexcept { for (int i = 0; i < v.size(); i++) v[i]--; } random_device seed_gen; mt19937_64 engine(seed_gen()); #pragma endregion // -------------------------------------- const int MAX_N = 1e6; int can_div[MAX_N] = {}; void init_prime() { can_div[1] = -1; for (int i = 2; i < MAX_N; i++) { if (can_div[i] != 0) continue; for (int j = i + i; j < MAX_N; j += i) can_div[j] = i; } } struct init_prime_ { init_prime_() { init_prime(); }; } init_prime_; inline bool is_prime(ll n) { if (n <= 1) return false; return !can_div[n]; } void factorization(int n, unordered_map &res) { if (n <= 1) return; if (!can_div[n]) { ++res[n]; return; } ++res[can_div[n]]; factorization(n / can_div[n], res); } int output(int a) { cout << "? " << a << endl; cin >> a; return a; } void solve() { int n; cin >> n; vector p; for (int i = 2; i <= n; i++) { if (not is_prime(i)) continue; int t = 1; while (t * i <= n) t *= i; p.push_back(t); } sort(all(p)); int ans = 0; rep(ti, 600) { int i = engine() % p.size(); int g = output(p[i]); if (g > 1) ans *= g; } cout << "! " << ans << endl; } int main() { solve(); }