/* Problem URL: https://codeforces.com/contest/2178/problem/E */ #include #include #include using namespace std; using namespace __gnu_pbds; template > using ordered_set = tree; #define V vector #define rmin(a, b) a = min(a, b) #define rmax(a, b) a = max(a, b) #define rep(i, lim) for (int i = 0; i < (lim); i++) #define nrep(i, s, lim) for (int i = s; i < (lim); i++) #define repv(i, v) for (auto &i : (v)) #define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; } #define sortv(v) sort(v.begin(), v.end()) #define all(v) (v).begin(), (v).end() using vi = vector; using vvi = vector; using vvvi = vector; using vvvvi = vector; using ll = long long; using vl = vector; using vvl = vector; using vvvl = vector; using vvvvl = vector; template auto operator<<(ostream &os, const vector &vec)->ostream& { os << vec[0]; for (size_t i = 1; i < vec.size(); i++) { os << ' ' << vec[i]; } os << '\n'; return os; } template auto operator>>(istream &is, vector &vec)->istream& { for (auto &i : vec) { is >> i; } return is; } template auto operator<<(ostream &os, const vector> &vec)->ostream& { for (auto &i : vec) { os << i[0]; for (size_t j = 1; j < i.size(); j++) { os << ' ' << i[j]; } os << '\n'; } return os; } template auto operator>>(istream &is, vector> &vec)->istream& { for (auto &i : vec) { for (auto &j : i) { is >> j; } } return is; } const int oo = INT32_MAX >> 1; const ll OO = INT64_MAX >> 1; void pre() { } #define TEST 1 void solve() { auto ask = [&](int l, int r) { cout << "? " << l << ' ' << r << endl; ll ans; cin >> ans; return ans; }; auto answer = [&](ll ans) { cout << "! " << ans << endl; fflush(stdout); }; int n; cin >> n; int l = 1; int r = n; while (l != r) { int low = l; int high = r; int ans = l; ll total = ask(l, r); while (low <= high) { int mid = (low + high) >> 1; ll cur = ask(l, mid); if (cur * 2 <= total) { ans = mid; low = mid + 1; continue; } high = mid - 1; } int sz1 = (ans - l + 1); int sz2 = (r - ans); if (sz1 <= sz2) { r = ans; continue; } l = ans + 1; } answer(ask(l, r)); } int main() { ios::sync_with_stdio(false); cin.tie(nullptr); pre(); int t; (TEST && cin >> t) || (t = 1); while (t--) { solve(); } }