#include <bits/stdc++.h> using namespace std; int main() { ios_base::sync_with_stdio(false); int t; cin >> t; while (t--) { int n; cin >> n; vector<vector<int>> a(n, vector<int>(n)); for (int i = 0; i < n; i++) { for (int j = 0; j < n; j++) { cin >> a[i][j]; } } bool ok = true; for (int i = 0; i < n; i++) { for (int j = 0; j < n; j++) { if (i+1 < n && a[i][j] == a[i+1][j]) { ok = false; } if (j+1 < n && a[i][j] == a[i][j+1]) { ok = false; } } } cout << (ok ? "Yes" : "No") << endl; } }