#include <bits/stdc++.h>
using namespace std;
const int INF = 0x3fffffff;
const int SINF = 0x7fffffff;
const long long LINF = 0x3fffffffffffffff;
const long long SLINF = 0x7fffffffffffffff;
const int MAXN = 2007;
int n;
int a[MAXN][MAXN];
int low[MAXN], pre[MAXN], kp;
bool ins[MAXN];
void init();
void input();
void work();
void tarjan(int now);
int main() {
  init();
  input();
  work();
}
void init() { ios::sync_with_stdio(false); }
void input() {
  scanf("%d", &n);
  for (int i = 1; i <= n; ++i)
    for (int j = 1; j <= n; ++j) scanf("%d", &a[j][i]);
}
void work() {
  memset(pre, -1, sizeof(pre));
  tarjan(1);
  for (int i = 1; i <= n; ++i) {
    if (pre[i] == -1) {
      cout << "NO" << endl;
      return;
    }
  }
  cout << "YES" << endl;
}
void tarjan(int now) {
  low[now] = pre[now] = ++kp;
  ins[now] = true;
  for (int v = 1; v <= n; ++v) {
    if (a[now][v] && (v ^ now)) {
      if (pre[v] == -1) {
        tarjan(v);
        low[now] = (((low[now]) < (low[v])) ? (low[now]) : (low[v]));
      } else if (ins[v])
        low[now] = (((low[now]) < (pre[v])) ? (low[now]) : (pre[v]));
    }
  }
  if (low[now] == pre[now]) {
    if (now ^ 1) {
      cout << "NO" << endl;
      exit(0);
    }
  }
}
