#include using namespace std; using ll = long long; using VI = vector; using VL = vector; using VS = vector; using VB = vector; using VVB = vector>; using VVI = vector; using VVL = vector; using PII = std::pair; using VPII = std::vector>; using PLL = std::pair; using VPLL = std::vector>; using TI3 = std::tuple; using TI4 = std::tuple; using TL3 = std::tuple; using TL4 = std::tuple; #define rep(i, n) for (int i = 0; i < (int)(n); i++) #define repr(i, n) for (int i = (int)(n)-1; i >= 0; i--) #define rep2(i, s, n) for (int i = (s); i < (int)(n); i++) #define rep3(i, s, n, d) for (int i = (s); i < (int)(n); i += (d)) #define allpt(v) (v).begin(), (v).end() #define allpt_c(v) (v).cbegin(), (v).cend() #define allpt_r(v) (v).rbegin(), (v).rend() #define allpt_cr(v) (v).crbegin(), (v).crend() const int mod1 = 1e9 + 7, mod2 = 998244353, mod3 = 1e9 + 9; const int mod = mod1; const ll inf = 1e18; const string wsp = " "; const string tb = "\t"; const string rt = "\n"; const string alphabets = "abcdefghijklmnopqrstuvwxyz"; template void show1dvec(const vector &v) { if (v.size() == 0) return; int n = v.size() - 1; rep(i, n) cout << v[i] << wsp; cout << v[n] << rt; return; } template void show2dvec(const vector> &v) { int n = v.size(); rep(i, n) show1dvec(v[i]); } template void show1dpair(const vector> &v) { int n = v.size(); rep(i, n) cout << v[i].first << wsp << v[i].second << rt; return; } template void pairzip(const vector> &v, vector &t, vector &s) { int n = v.size(); rep(i, n) { t.push_back(v[i].first); s.push_back(v[i].second); } return; } template void maxvec(vector &v) { T s = v[0]; int n = v.size(); rep(i, n - 1) { if (s > v[i + 1]) { v[i + 1] = s; } s = v[i + 1]; } } template bool myfind(T t, S s) { return find(t.cbegin(), t.cend(), s) != t.cend(); } bool check(int y, int x, int h, int w) { return 0 <= y && y < h && 0 <= x && x < w; } bool iskadomatsu(int a, int b, int c) { return (a != b && b != c && c != a) && ((a > b && b < c) || (a < b && b > c)); } double euc_dist(PII a, PII b) { return sqrt(pow(a.first - b.first, 2) + pow(a.second - b.second, 2)); } VS split(string s, char c) { VS ret; string part; s += c; rep(i, s.length()) { if (s[i] == c) { if (part != "") ret.emplace_back(part); part = ""; } else if (s[i] != c) { part += s[i]; } } return ret; } template ll pow_mod(T p, S q, R mod = 1ll) { ll ret = 1, r = p; while (q) { if (q % 2) ret *= r, ret %= mod; r = (r * r) % mod, q /= 2; } return ret % mod; } template ll pow_no_mod(T p, S q) { ll ret = 1, r = p; while (q) { if (q % 2) ret *= r; r = (r * r), q /= 2; } return ret; } void make_frac_tables(VL &frac_list, VL &frac_inv_list) { rep(i, frac_list.size() - 1) { frac_list[i + 1] *= frac_list[i] * (i + 1); frac_list[i + 1] %= mod; frac_inv_list[i + 1] *= frac_inv_list[i] * pow_mod(i + 1, mod - 2, mod); frac_inv_list[i + 1] %= mod; } } pair make_frac_tables(int n) { VL frac_list(n + 1, 1), frac_inv_list(n + 1, 1); rep(i, n) { frac_list[i + 1] *= frac_list[i] * (i + 1); frac_list[i + 1] %= mod; frac_inv_list[i + 1] *= frac_inv_list[i] * pow_mod(i + 1, mod - 2, mod); frac_inv_list[i + 1] %= mod; } return make_pair(frac_list, frac_inv_list); } // ll comb(int a, int b, const VL &frac_list, const VL &frac_inv_list) { // if (a < b) return 0; // if (b < 0) return 0; // ll ret = frac_list[a]; // ret *= frac_inv_list[b]; // ret %= mod; // ret *= frac_inv_list[a - b]; // ret %= mod; // return ret; // } void djkstra(int n, int s, int t, const vector> &connect) { const int intm = 1e9; vector shortest(n, intm); shortest[s] = 0; vector search = {s}; vector new_search; while (!search.empty()) { for (auto i : search) { for (auto j : connect[i]) { if (shortest[j] > 1 + shortest[i]) { shortest[j] = 1 + shortest[i]; new_search.emplace_back(j); } } } search.clear(); search = new_search; new_search.clear(); // show1dvec(search); // show1dvec(shortest); } if (shortest[t] == intm) shortest[t] = -1; printf("%d\n", shortest[t]); } class RangeMinorMaxorSumQuery // 0-index { int const intmax = 2147483647; int const intmin = 0; vector sgt; int n; int k; public: RangeMinorMaxorSumQuery(int n1, int f = -1) { if (f == -1) f = intmax; else if (f == 0) f = intmin; int na = 1; int ka = 0; while (na < n1) { na *= 2; ka++; } for (int i = 0; i < 2 * na; i++) sgt.push_back(f); n = na; k = ka; } void update_sum(int i, double x) { i += n; sgt[i] = x; while (i > 1) { i /= 2; sgt[i] = sgt[2 * i] + sgt[2 * i + 1]; } } double getsum(int a, int b, int k = 1, int l = 0, int r = -1) //閉区間 l <= x < r とする { if (r == -1) r = n; if (r <= a || b <= l) return intmin; if (a == l && b == r) return sgt[k]; else return getsum(a, min(b, (l + r) / 2), 2 * k, l, (l + r) / 2) + getsum(max(a, (l + r) / 2), b, 2 * k + 1, (l + r) / 2, r); } void printsegtree() { for (int i = 0; i < 2 * n; i++) { cout << sgt[i] << " "; } cout << endl; } }; struct node { int parent = -1; ll weight = 0; int subtree = 1; VPII children; VPII connect; node(int n) { parent = -1; weight = 0; subtree = 1; children; connect; } }; int ask(int v) { cout << "? " << v << endl; int res; cin >> res; return res; } void answer(int v) { cout << "! " << v << endl; } int main() { cin.tie(0); ios::sync_with_stdio(false); #ifdef DEBUG cout << "DEBUG MODE" << endl; ifstream in("input.txt"); // for debug cin.rdbuf(in.rdbuf()); // for debug #endif int turn = 1; if (ask(46) == 0) { answer(46); return 0; } if (ask(46) == -1) { rep(_, 60) { if (ask(0) == 0) { answer(turn); return 0; } ++turn; } } // int up = 1e9 + 10; // int down = 0; // int mid; // while (1) { // mid = (up + down) / 2; // auto ret = ask(mid); // if (ret == 0) { // answer(turn); // return 0; // } // } // show1dvec(dp); // show1dvec(before); return 0; }