/*input 2 2 0 0 0 0 2 0 1 1 0 */ #include <bits/stdc++.h> #include <ext/pb_ds/assoc_container.hpp> using namespace std; using namespace __gnu_pbds; #define REP(i,j,k) for(int i = j ; i < k ; ++i) #define RREP(i,j,k) for(int i = j ; i >=k ; --i) #define A first #define B second #define mp make_pair #define pb emplace_back #define PII pair<int , int> #define MEM(i,j) memset(i , j , sizeof i) #define ALL(i) i.begin() , i.end() #define DBGG(i,j) cout << i << " " << j << endl #define DB4(i,j,k,l) cout << i << " " << j << " " << k << " " << l << endl #define IOS cin.tie(0) , cout.sync_with_stdio(0) #define endl "\n" ///------------------------------------------------------------ #define MAX 500 #define INF 0x3f3f3f3f int t , n , m , x[MAX][MAX]; int32_t main(){ IOS; cin >> t; while(t -- ){ cin >> n , m = n; REP(i , 1 , n + 1) REP(j , 1 , m + 1) cin >> x[i][j]; int ok = 1; REP(i , 1 , n + 0) REP(j , 1 , m + 1) if(x[i][j] == x[i + 1][j]) ok = 0; REP(i , 1 , n + 1) REP(j , 1 , m + 0) if(x[i][j] == x[i][j + 1]) ok = 0; if(ok == 1) cout << "Yes" << endl; else cout << "No" << endl; } return 0; }