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

const int N = 1e5 + 50;

int T, n, son[N * 60][2], cnt;
ll a[N];

void insert (ll x) {
    int p = 0;
    for (int i = 60; i >= 0; i --) {
        int v = x >> i & 1;
        if (! son[p][v]) son[p][v] = ++ cnt;
        p = son[p][v];
    }
}

ll query (ll x) {
    ll p = 0, res = 0;
    for (int i = 60; i >= 0; i --) {
        int v = x >> i & 1;
        if (son[p][v ^ 1]) {
            res |= 1ll << i;
            p = son[p][v ^ 1];
        }else p = son[p][v];
    }
    return res;
}

int main() {
#ifdef LOCAL
    freopen("in.in", "r", stdin);
    freopen("out.out", "w", stdout);
#endif
    scanf ("%d", &T);
    while (T --) {
        scanf ("%d", &n);
        for (int i = 1; i <= n; i ++) 
            scanf ("%lld", &a[i]);
        
        insert (0);
        ll ans = 0;
        for (int i = 1; i <= n; i ++) {
            a[i] ^= a[i - 1];
            ans = max (ans, query (a[i]));
            insert (a[i]);
        }
        printf("%lld\n", ans);
        for (int i = 0; i <= cnt; i ++) 
            memset (son[i], 0, sizeof (son[i]));
        cnt = 0;
    }
    return 0;
}