#include <iostream>
#include <map>
#include <set>
#include <vector>

using namespace std;
typedef long long ll;
int main()
{
    int t;
    cin >> t;
    while(t--) {
        ll a, b;
        cin >> a >> b;
        ll result = 0;
        for(ll i = 32; i >= 0; i--) {
            if((a & (1 << i)) == (b & (1 << i))) {
                result |= (a & (1 << i));
            }
            else {
                break;
            }
        }
        cout << result << endl;
    }
        return 0;
}