#pragma region #pragma GCC target("avx2") #pragma GCC optimize("03") #pragma GCC optimize("unroll-loops") #include using namespace std; typedef long double ld; typedef long long ll; typedef unsigned long long ull; #define endl "\n" #define FOR(i,a,b) for(int i=(a);i<=(b);i++) #define PII pair #define PLL pair #define VPII vector #define VPLL vector #define ALL(x) (x).begin(), (x).end() constexpr int INF=1<<30; constexpr ll LINF=1LL<<60; constexpr ll mod=1e9+7; constexpr int NIL = -1; templateinline bool chmax(T &a, const T &b) { if (ainline bool chmin(T &a, const T &b) { if (b need; vector remained; int main(){ cin.tie(0); ios::sync_with_stdio(false); //cout << fixed << setprecision(15); auto ask = [&]() { vector v = remained; v.insert(v.end()-1, need.begin(), need.end()); sort(v.begin(), v.end()); cout << "? " << v.size() << endl; for(auto &e: v) cout << e << " "; cout << endl; }; int n; cin >> n; FOR(i,1,n) remained.emplace_back(i); while(remained.size() != 0) { ask(); int ans; cin >> ans; if(ans) { need.push_back(remained.back()); } remained.erase(remained.end()); } sort(ALL(need)); cout << "! " << need.size() << endl; for(auto &e: need) cout << e << " "; cout << endl; return 0; }