#include <iostream> using namespace std; int main() { int n; cin >> n; int a[25][25]; for (int i = 0; i < n; i++) { for (int j = 0; j < n; j++) { cin >> a[i][j]; } } int target = 0; for (int j = 0; j < n; j++) { target += a[0][j]; } for (int i = 0; i < n; i++) { int sum = 0; for (int j = 0; j < n; j++) { sum += a[i][j]; } if (sum != target) { cout << "No" << endl; return 0; } } for (int j = 0; j < n; j++) { int sum = 0; for (int i = 0; i < n; i++) { sum += a[i][j]; } if (sum != target) { cout << "No" << endl; return 0; } } int sum1 = 0; for (int i = 0; i < n; i++) { sum1 += a[i][i]; } if (sum1 != target) { cout << "No" << endl; return 0; } int sum2 = 0; for (int i = 0; i < n; i++) { sum2 += a[i][n - 1 - i]; } if (sum2 != target) { cout << "No" << endl; return 0; } cout << "Yes" << endl; return 0; }