#include <bits/stdc++.h>

using namespace std;

int main() {
    cin.tie(nullptr);
    cout.tie(nullptr);
    iostream::sync_with_stdio(false);

    int t;
    cin >> t;
    while (t--) {
        int n;
        cin >> n;
        vector<int> as(n), bs(n);
        for (int i = 0; i < n; ++i) {
            cin >> as[i];
        }
        for (int i = 0; i < n; ++i) {
            cin >> bs[i];
        }

        sort(as.begin(), as.end());
        sort(bs.begin(), bs.end());
        int max_ans = 0;
        for (int shift = 0; shift < n; ++shift) {
            int cur = INT_MAX;
            for (int j = 0; j < n; ++j) {
                cur = min(cur, abs(as[j] - bs[(j + shift) % n]));
            }
            max_ans = max(max_ans, cur);
        }
        cout << max_ans << '\n';
    }
}