#include <bits/stdc++.h>
using namespace std;

#define int long long
#define rep(i, n) for (int i = 0; i < (int) (n); i++)
#define reps(i, n) for (int i = 1; i <= (int) (n); i++)
#define all(x) (x).begin(), (x).end()
#define uniq(x) (x).erase(unique(all(x)), (x).end())
#define bit(n) (1LL << (n))
#define dump(x) cerr << #x " = " << (x) << endl
using vint = vector<int>;
using vvint = vector<vint>;
using pint = pair<int, int>;
using vpint = vector<pint>;
template<typename T> using priority_queue_rev = priority_queue<T, vector<T>, greater<T>>;
constexpr double PI = 3.1415926535897932384626433832795028;
constexpr int DY[9] = {0, 1, 0, -1, 1, 1, -1, -1, 0};
constexpr int DX[9] = {1, 0, -1, 0, 1, -1, -1, 1, 0};
int sign(int x) { return (x > 0) - (x < 0); }
int gcd(int a, int b) {
    while (b) { swap(a %= b, b); }
    return a;
}
int lcm(int a, int b) { return a / gcd(a, b) * b; }
int cdiv(int a, int b) { return (a - 1 + b) / b; }
template<typename T> void fin(T mes) {
    cout << mes << endl;
    exit(0);
}
template<typename T, typename U> bool chmax(T &a, const U &b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}
template<typename T, typename U> bool chmin(T &a, const U &b) {
    if (b < a) {
        a = b;
        return true;
    }
    return false;
}
template<typename T, typename U> ostream &operator<<(ostream &os, const pair<T, U> &rhs) {
    os << "(" << rhs.first << ", " << rhs.second << ")";
    return os;
}
template<typename T> ostream &operator<<(ostream &os, const vector<T> &rhs) {
    os << "{";
    for (auto itr = rhs.begin(); itr != rhs.end(); itr++) {
        os << *itr << (next(itr) != rhs.end() ? ", " : "");
    }
    os << "}";
    return os;
}
template<typename T> ostream &operator<<(ostream &os, const deque<T> &rhs) {
    os << "{";
    for (auto itr = rhs.begin(); itr != rhs.end(); itr++) {
        os << *itr << (next(itr) != rhs.end() ? ", " : "");
    }
    os << "}";
    return os;
}
template<typename T> ostream &operator<<(ostream &os, const set<T> &rhs) {
    os << "{";
    for (auto itr = rhs.begin(); itr != rhs.end(); itr++) {
        os << *itr << (next(itr) != rhs.end() ? ", " : "");
    }
    os << "}";
    return os;
}
template<typename T, typename U> ostream &operator<<(ostream &os, const map<T, U> &rhs) {
    os << "{";
    for (auto itr = rhs.begin(); itr != rhs.end(); itr++) {
        os << *itr << (next(itr) != rhs.end() ? ", " : "");
    }
    os << "}";
    return os;
}
struct setup {
    static constexpr int PREC = 20;
    setup() {
        cout << fixed << setprecision(PREC);
        cerr << fixed << setprecision(PREC);
    };
} setup;

template<int N>
std::vector<std::bitset<N>> xor_eliminate(std::vector<std::bitset<N>> src) {
    std::vector<std::bitset<N>> ret;
    for (int i = src.size() - 1; i >= 0; i--) {
        for (int j = 0; j < i; j++) {
            int x = src[j]._Find_first(), y = src[j + 1]._Find_first();
            if (x < y) { src[j + 1] ^= src[j]; }
            if (x <= y) { src[j] ^= src[j + 1]; }
        }
        if (src[i].none()) { break; }
        ret.emplace_back(src[i]), src.pop_back();
    }
    for (int i = ret.size() - 1; i > 0; i--) {
        for (int j = i - 1; j >= 0; j--) {
            if (ret[j][ret[i]._Find_first()]) { ret[j] ^= ret[i]; }
        }
    }
    return ret;
}

signed main() {
    int N;
    cin >> N;
    vint A(N);
    rep(i, N) { cin >> A[i]; }
    using bset = bitset<60>;
    bset sum(0);
    vector<bset> a(N);
    rep(i, N) { a[i] = A[i], sum ^= a[i]; }
    rep(i, N) { a[i] &= ~sum; }
    auto bit_reverse = [](bset &bs) {
        rep(i, 30) {
            bool tmp = bs[60 - i - 1];
            bs[60 - i - 1] = bs[i];
            bs[i] = tmp;
        }
    };
    rep(i, N) { bit_reverse(a[i]); }
    vector<bset> b = xor_eliminate<60>(a);
    bset ans(0);
    rep(i, b.size()) {
        if (!ans[b[i]._Find_first()]) { ans ^= b[i]; }
    }
    bit_reverse(ans);
    cout << ans.to_ullong() + (ans ^ sum).to_ullong() << endl;
}


Measured memory_bytes: 5608