112634

import java.io.IOException;
import java.util.LinkedList;
import java.util.Scanner;

public class task112634 {
    public static void BFS(int s) {
        LinkedList<Integer> q = new LinkedList<Integer>();
        d[s] = 0;
        q.addLast(s);
        while (!q.isEmpty()) {
            int vertex =  q.pollFirst();
            for (int j = 0; j < n; j++) {
                if (G[vertex][j] == 1 && d[j] == -1) {
                    d[j] = d[vertex] + 1;
                    q.addLast(j);
                }
            }
        }
    }

    static int n;
    static int[] d;
    static int[][] G;
    public static void main(String[] args) throws IOException {
        Scanner in = new Scanner(System.in);
        n = in.nextInt();
        int x = 0;
        int q=0;
        int[] a = new int[n];
        d = new int[n];
        for (int i = 0; i < n; i++) {
            d[i] = -1;
        }
        G = new int[n][n];
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                G[i][j] = in.nextInt();
            }
        }
        BFS(0);
        for (int i = 0; i < a.length; i++) {
            if(d[i]==-1) {
                System.out.println("NO");
                q=0;
                break;
            }else {
                q=1;
            }
        }
        if(q==1)System.out.println("YES");
    }

}