#include #define rep(i,n) for(int i = 0; i < (n); i++) using namespace std; using ll = long long; using ld = long double; int main(){ cin.tie(0); ios::sync_with_stdio(0); ll N,K; cin >> N >> K; vector A(N); rep(i,N) cin >> A[i]; int N0 = N / 2, N1 = N - N / 2; vector A0, A1; rep(i,N0) A0.push_back(A[i]); rep(i,N1) A1.push_back(A[i + N0]); set> st0; rep(S,1<