#include <bits/stdc++.h>
using namespace std;
using lint = long long int;
using pint = pair<int, int>;
using plint = pair<lint, lint>;
struct fast_ios { fast_ios(){ cin.tie(0); 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)
template<typename T> istream &operator>>(istream &is, vector<T> &vec){ for (auto &v : vec) is >> v; return is; }
template<typename T> ostream &operator<<(ostream &os, const vector<T> &vec){ os << "["; for (auto v : vec) os << v << ","; os << "]"; return os; }
template<typename T> ostream &operator<<(ostream &os, const deque<T> &vec){ os << "deq["; for (auto v : vec) os << v << ","; os << "]"; return os; }
template<typename T> ostream &operator<<(ostream &os, const set<T> &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; }
template<typename T> ostream &operator<<(ostream &os, const unordered_set<T> &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; }
template<typename T> ostream &operator<<(ostream &os, const multiset<T> &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; }
template<typename T> ostream &operator<<(ostream &os, const unordered_multiset<T> &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; }
template<typename T1, typename T2> ostream &operator<<(ostream &os, const pair<T1, T2> &pa){ os << "(" << pa.first << "," << pa.second << ")"; return os; }
template<typename TK, typename TV> ostream &operator<<(ostream &os, const map<TK, TV> &mp){ os << "{"; for (auto v : mp) os << v.first << "=>" << v.second << ","; os << "}"; return os; }
template<typename TK, typename TV> ostream &operator<<(ostream &os, const unordered_map<TK, TV> &mp){ os << "{"; for (auto v : mp) os << v.first << "=>" << v.second << ","; os << "}"; return os; }
template<typename T> void ndarray(vector<T> &vec, int len) { vec.resize(len); }
template<typename T, typename... Args> void ndarray(vector<T> &vec, int len, Args... args) { vec.resize(len); for (auto &v : vec) ndarray(v, args...); }
template<typename T> bool mmax(T &m, const T q) { if (m < q) {m = q; return true;} else return false; }
template<typename T> bool mmin(T &m, const T q) { if (m > q) {m = q; return true;} else return false; }
template<typename T1, typename T2> pair<T1, T2> operator+(const pair<T1, T2> &l, const pair<T1, T2> &r) { return make_pair(l.first + r.first, l.second + r.second); }
template<typename T1, typename T2> pair<T1, T2> operator-(const pair<T1, T2> &l, const pair<T1, T2> &r) { return make_pair(l.first - r.first, l.second - r.second); }
#define dbg(x) cerr << #x << " = " << (x) << " (L" << __LINE__ << ") " << __FILE__ << endl;
#define ALL(x) (x).begin(), (x).end()

constexpr int D = 60;
constexpr int Wmax = 100010;

vector<bitset<Wmax>> gauss_jordan(int W, vector<bitset<Wmax>> mtr)
{
    int H = mtr.size(), c = 0;
    for (int h = 0; h < H; h++, c++)
    {
        if (c == W) break;
        int piv = -1;
        for (int j = h; j < H; j++) if (mtr[j][c]) {
                piv = j; break;
        }
        if (piv == -1) { h--; continue; }
        swap(mtr[piv], mtr[h]);
        for(int hh = h + 1; hh < H; hh++) {
            if (mtr[hh][c]) mtr[hh] = mtr[hh] xor mtr[h];
        }
    }
    return mtr;
}


int main()
{
    int N;
    cin >> N;
    vector<lint> A(N);
    cin >> A;

    lint ret = 0, ret2 = 0;
    vector<bitset<Wmax>> mtr;
    IREP(d, D)
    {
        int c = 0;
        for (auto a : A) c += !!(a & (1LL << d));
        if (c % 2)
        {
            ret += (1LL << d);
            continue;
        }
        if (c == 0) continue;

        bitset<Wmax> madd;
        REP(i, N) if (A[i] & (1LL << d)) madd[i] = 1;
        madd[N] = 1;
        mtr.push_back(madd);

        auto m2 = gauss_jordan(N + 1, mtr);
        bool flg = true;
        REP(h, m2.size()) if (m2[h]._Find_first() == N) flg = false;

        if (flg)
        {
            ret += (1LL << d);
            ret2 += (1LL << d);
        }
        else mtr.pop_back();
    }
    cout << ret + ret2 << endl;
}


Measured memory_bytes: 2692