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

static int N;
static int A[100][100];

int main(void)
{
    int T;
    cin >> T;
    while (T--) {
        cin >> N;
        bool good = true;
        for (int i = 0; i < N; i++) {
            for (int j = 0; j < N; j++) {
                cin >> A[i][j];
                if (i > 0 && A[i-1][j] == A[i][j])
                    good = false;
                if (j > 0 && A[i][j-1] == A[i][j])
                    good = false;
            }
        }
        printf("%s\n", good ? "Yes" : "No");
    }
    return 0;
}