#include using namespace std; using lint = long long; using pint = pair; using plint = pair; struct fast_ios { fast_ios() { cin.tie(nullptr), ios::sync_with_stdio(false), cout << fixed << setprecision(20); }; } fast_ios_; #define FOR(i, begin, end) for (int i = (begin), i##_end_ = (end); i < i##_end_; i++) #define IFOR(i, begin, end) for (int i = (end)-1, i##_begin_ = (begin); i >= i##_begin_; i--) #define REP(i, n) FOR(i, 0, n) #define IREP(i, n) IFOR(i, 0, n) #define ALL(x) (x).begin(), (x).end() // template void ndarray(vector& vec, const V& val, int len) { vec.assign(len, val); } template void ndarray(vector& vec, const V& val, int len, Args... args) { vec.resize(len), for_each(begin(vec), end(vec), [&](T& v) { ndarray(v, val, args...); }); } template bool chmax(T& m, const T q) { return m < q ? (m = q, true) : false; } template bool chmin(T& m, const T q) { return m > q ? (m = q, true) : false; } template pair operator+(const pair& l, const pair& r) { return make_pair(l.first + r.first, l.second + r.second); } template pair operator-(const pair& l, const pair& r) { return make_pair(l.first - r.first, l.second - r.second); } template vector srtunq(vector vec) { return sort(vec.begin(), vec.end()), vec.erase(unique(vec.begin(), vec.end()), vec.end()), vec; } template istream& operator>>(istream& is, vector& vec) { return for_each(begin(vec), end(vec), [&](T& v) { is >> v; }), is; } // output template ostream& dmpseq(ostream&, const T&, const string&, const string&, const string&); #if __cplusplus >= 201703L template ostream& operator<<(ostream& os, const tuple& tpl) { return apply([&os](auto&&... args) { ((os << args << ','), ...); }, tpl), os; } #endif // template ostream& operator<<(ostream& os, const pair& p) { return os << '(' << p.first << ',' << p.second << ')'; } template ostream& operator<<(ostream& os, const vector& x) { return dmpseq, T>(os, x, "[", ",", "]"); } template ostream& operator<<(ostream& os, const deque& x) { return dmpseq, T>(os, x, "deq[", ",", "]"); } template ostream& operator<<(ostream& os, const set& x) { return dmpseq, T>(os, x, "{", ",", "}"); } template ostream& operator<<(ostream& os, const unordered_set& x) { return dmpseq, T>(os, x, "{", ",", "}"); } template ostream& operator<<(ostream& os, const multiset& x) { return dmpseq, T>(os, x, "{", ",", "}"); } template ostream& operator<<(ostream& os, const map& x) { return dmpseq, pair>(os, x, "{", ",", "}"); } template ostream& operator<<(ostream& os, const unordered_map& x) { return dmpseq, pair>(os, x, "{", ",", "}"); } template ostream& dmpseq(ostream& os, const T& seq, const string& pre, const string& sp, const string& suf) { return os << pre, for_each(begin(seq), end(seq), [&](V x) { os << x << sp; }), os << suf; } template void print(const vector& x) { dmpseq, T>(cout, x, "", " ", "\n"); } #ifdef HITONANODE_LOCAL #define dbg(x) cerr << #x << " = " << (x) << " (L" << __LINE__ << ") " << __FILE__ << endl #else #define dbg(x) {} #endif constexpr int D = 30; int main() { int N, T; cin >> N >> T; map v; v[T] = 0; while (N--) { int a; cin >> a; map vnxt; for (auto [msk, val] : v) { chmax(vnxt[msk | a], val + (msk | a) - msk); chmax(vnxt[msk & a], val + msk - (msk & a)); } v = vnxt; } lint ret = 0; for (auto [msk, val] : v) chmax(ret, val); cout << ret << '\n'; }