#include <bits/stdc++.h>

using namespace std;

#define int long long
#define rep(i, s, e) for (int i = s; i <= e; ++i)
#define drep(i, s, e) for (int i = s; i >= e; --i)
#define file(a) freopen(#a".in", "r", stdin), freopen(#a".out", "w", stdout)
#define pv(a) cout << #a << " = " << a << endl
#define pa(a, l, r) cout << #a " : "; rep(_, l, r) cout << a[_] << ' '; cout << endl

const int N = 1e6 + 10;
const int W = 61;

int read() {
  int x = 0, f = 1; char c = getchar();
  for (; c < '0' || c > '9'; c = getchar()) if (c == '-') f = -1;
  for (; c >= '0' && c <= '9'; c = getchar()) x = x * 10 + c - 48;
  return x * f;
}

int n, a[N], s, ans;

namespace base {

  int dat[N];

  void clear() { fill(dat, dat + W, 0); }
  
  void ins(int x) {
    drep(i, __lg(x), 0) if (x >> i & 1) {
      if (dat[i]) x ^= dat[i];
      else { dat[i] = x; break; }
    }
  }

  bool ask(int x) {
    drep(i, __lg(x), 0) if (x >> i & 1) x ^= dat[i];
    return !x;
  }

}

signed main() {
  n = read();
  rep(i, 1, n) a[i] = read(), s ^= a[i];
  rep(i, 0, W - 1) if (~s >> i & 1) {
    rep(j, 1, n) base::ins(a[j] & ((1ll << i + 1) - 1));
    if (base::ask((1ll << i) - 1)) ans = s ^ ((1ll << i + 1) - 1);
    base::clear();
  }
  printf("%lld\n", ans);
  return 0;
}