#include using namespace std; int main() { ios::sync_with_stdio(false); cin.tie(nullptr); int n; cin >> n; vector> a(n, vector(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++) { for (int k = 0; k < n; k++) { if (a[a[i][j]][k] != a[i][a[j][k]]) { ok = false; } } } } bool ok2 = false; int e = -1; for (int i = 0; i < n; i++) { bool cur = true; for (int j = 0; j < n; j++) { if (a[i][j] != j || a[i][j] != a[j][i]) { cur = false; } } if (cur) { e = i; ok2 = true; } } if (!ok || !ok2) { cout << "No" << '\n'; return 0; } for (int i = 0; i < n; i++) { bool cur = false; for (int j = 0; j < n; j++) { if (a[i][j] == e && a[j][i] == e) { cur = true; } } if (!cur) { cout << "No" << '\n'; return 0; } } cout << "Yes" << '\n'; }