12.05 3

#include <iostream>
#include <cmath>
#include <algorithm>
#include <vector>
using namespace std;
int main() {
    int n;
    cin >> n;
    int a[n][n];
    for(int i = 0; i < n; i++){
        for(int j = 0; j < n; j++){
            cin >> a[i][j];
        }
    }
    int ans = 1;
    for(int i = 0; i < n; i++){
        for(int j = 0; j < n; j++){
            if(a[i][j] != a[j][i]){
                    ans = 0;
            }
        }
    }
    if(ans ==0){
        cout<< "no"<<endl;
    }
    if(ans == 1){
        cout<<"yes"<<endl;
    }
    return 0;
}