#include<bits/stdc++.h>
#define rep(i,l,r) for (int i(l), i##end(r); i <= i##end; ++i)
#define per(i,r,l) for (int i(r), i##end(l); i >= i##end; --i)
#define ll long long
#define ull unsigned long long
#define fi first
#define se second
#define eb emplace_back
#define File(filename) freopen(filename".in", "r", stdin), freopen(filename".out", "w", stdout)
using namespace std;
template <typename Tx> inline void read(Tx &x) {x = 0; bool f = 0; char ch = getchar(); while (ch < '0' || ch > '9') f ^= ch == '-', ch = getchar(); while (ch <= '9' && ch >= '0') x = x * 10 + ch - '0', ch = getchar(); if (f) x = -x;}
template <typename Tx, typename ...Ty> inline void read(Tx &x, Ty &...y) {read(x); read(y...);}
template <typename Tx> inline void O_write(Tx x) {if (x > 9) O_write(x / 10); putchar('0' + x % 10);}
template <typename Tx> inline void write(Tx x, char ch = '\n') {O_write(x < 0 ? (putchar('-'), -x) : x); putchar(ch);}
template <typename Tx> inline void cmax(Tx &x, Tx y) {if (x < y) x = y;}
template <typename Tx> inline void cmin(Tx &x, Tx y) {if (x > y) x = y;}
namespace Main {

const int N = 1e6 + 9;
const int LogW = 60;
int n;
ull p[LogW + 1], ans;

bool chk(ull x) {
    per (i, LogW, 0) if (x >> i & 1) {
        x ^= p[i];
    }
    return x == 0 ? 1 : 0;
}
void upd(ull x) {
    per (j, LogW, 0) if (x >> j & 1) {
        if (p[j]) x ^= p[j];
        else {
            p[j] = x;
            break;
        }
    }
}

void skymaths() {
    read(n);
    rep (i, 1, n) { ull x;
        read(x);
        ans ^= x;
        upd(x);
    }
    per (i, LogW, 0) {
        if (chk((1ll << i) - 1)) {
            ans ^= (1ll << i + 1) - 1;
            write(ans);
            return ;
        }
        else {
            if (p[i]) {
                ull x = p[i];
                p[i] = x;
                if (x) {
                    x ^= 1ll << i;
                    upd(x);
                }
            }
        }
    }
}

signed main() {
    // freopen("a.in", "r", stdin);
    int T = 1;
    // read(T);
    while (T--) {
        skymaths();
    }
    return 0;
} } signed main() { Main::main(); return 0;}