#define _CRT_SECURE_NO_WARNINGS
#include "bits/stdc++.h"
using namespace std;
#define all(a) a.begin(), a.end()
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
typedef long double ld;
#define int long long
pair<bool, pair<vector<pair<int, int>>, vector<pair<int, int>>>> ok(vector<pair<int, int>>& b, int bit) {
    int cnt[2][2] = {};
    vector<pair<int, int>> bit1, bit0;
    for (int i = 0; i < (int)b.size(); i++) {
        cnt[(b[i].first >> bit) & 1ll][b[i].second]++;
        int bt = (b[i].first >> bit) & 1ll;
        if (bt && b[i].second == 1 || !bt && b[i].second == 0) {
            bit1.push_back(b[i]);
        }
        else {
            bit0.push_back(b[i]);
        }
    }
    if (cnt[0][0] == cnt[1][1] && cnt[1][0] == cnt[0][1]) {
        return { true, {bit1, bit0} };
    }
    else {
        return { false, {{},{}} };
    }
}
signed main() {
#ifdef _DEBUG
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    int t; cin >> t;
    while (t--) {
        int n;
        cin >> n;
        vector<vector<pair<int, int>>> group(1);
        for (int i = 0; i < n; i++) {
            int x; cin >> x;
            group[0].push_back({ x, 0 });
        }
        for (int i = 0; i < n; i++) {
            int x; cin >> x;
            group[0].push_back({x, 1});
        }
        int ans = 0;
        for (int bit = 31; bit >= 0; bit--) {
            bool psh = true;
            vector<vector<pair<int, int>>> new_group;
            for (auto& i : group) {
                auto ret = ok(i, bit);
                if (ret.first == false) {
                    psh = false;
                    break;
                }
                if(!ret.second.first.empty())new_group.push_back(ret.second.first);
                if (!ret.second.second.empty())new_group.push_back(ret.second.second);
            }
            if (psh) {
                ans |= (1ll << bit);
                group.swap(new_group);
            }
            new_group.clear();
        }
        cout << ans << '\n';
    }
}