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

#define pb push_back
#define fi first
#define se second
#define all(x) (x).begin(), (x).end()
#define Sz(x) (int)(x).size()
#define bit(x) (1ll << (x))
using ll = long long;
using db = double;
using ull = unsigned long long;
using pii = pair<int, int>;
using vi = vector<int>;
using vii = vector<vi>;
using vl = vector<ll>;
using vll = vector<vl>;
using vs = vector<string>;
using vd = vector<db>;
mt19937 mrand(time(0));

void solve(void)
{
	int n;
	cin >> n;
	vi l(n + 2), r(n + 2);
	for (int i = 1; i <= n; i++)
		cin >> l[i] >> r[i];

	int pre = 0;
	for (int j = 30; j >= 0; j--)
	{
		auto check = [&](int b, int i)
		{
			int now = pre + bit(b);
			int u = l[i];
			if ((u & now) == now) return (bool)1;
			int a = (bit(b) - 1) & u;
			u = (u | now) - a;
			return u <= r[i];
		};
		int mark = 1;
		for (int i = 1; i <= n; i++)
			if (!check(j, i))
				mark = 0;
		if (mark) pre += bit(j);
	}
	cout << pre << "\n";
}

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

	// cout << fixed << setprecision(10);

	int T = 1;
	cin >> T;
	for (int i = 1; i <= T; i++)
	solve();

	return 0;
}