#include <iostream>
#include <algorithm>
#include <cassert>

using namespace std;

const int MAXN = 100;

int Tn, ret, a[MAXN][MAXN], f[MAXN][MAXN], n;

int main(int argc, const char * argv[]) {
    cin >> Tn;
    assert(1 <= Tn && Tn <= 10);
    while (Tn--) {
        cin >> n;
        assert(1 <= n && n <= 70);
        for(int i = 1; i <= n; i++)
            for(int j = 1; j <= n; j++) {
                cin >> a[i][j];
                assert(1 <= a[i][j] && a[i][j] <= 1000000000);
            }
        ret = 0;
        
        /*
         Preprocess for calculation XOR on a submatrix fast.
         */
        
        for(int i = 1; i <= n; i++)
            for(int j = 1; j <= n; j++)
                f[i][j] = f[i - 1][j] ^ f[i][j - 1]  ^ f[i - 1][j - 1] ^ a[i][j];
        
        /*
         Brute-force all the possible submatrices and get the best one.
         */
        
        for(int x1 = 1; x1 <= n; x1++)
            for(int y1 = 1; y1 <= n; y1++)
                for(int x2 = x1; x2 <= n; x2++)
                    for(int y2 = y1; y2 <= n; y2++)
                        ret = max(ret, f[x2][y2] ^ f[x1 - 1][y2] ^ f[x2][y1 - 1] ^ f[x1 - 1][y1 - 1]);
        
        cout << ret << endl;
    }
    return 0;
}