lefkaritika 2017

#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;
int main() {
    int a;
    cin>>a;
    bool n=1;
    int y;
    int x ,s;
    for(int k=0;k<a;k++){
        n = 1;
        cin>>y;
        int c[y];
        string w;
        for(int i=0;i<y;i++){
            cin>>w;
            c[i] = atoi(w.c_str());
            for(int j=0;j<y/2;j++){
                if(w[j] != w[y-(j+1)]){
                    n = 0;
                        break;
                }
            }
        }
        for(int i=0;i<y/2;i++){
            if(c[i] != c[y - (i+1)]){
                n = 0;
                    break;
            }
        }

        if(n == 1){
            cout<<"YES"<<endl;
        }
        else{
            cout<<"NO"<<endl;
        }
    }
    return 0;
}