#include<iostream>
using namespace std;
const int mod=998244353;
int n,f0[3010],f1[3010],f[3010][3010];
char s[3010][3010];
int main()
{
	ios::sync_with_stdio(false);
	cin.tie(0);
	cin>>n;
	for(int i=1;i<=n;i++)
	{
		cin>>s[i]+1;
	}
	for(int i=f[0][0]=1;i<=n;i++)
	{
		int p=n+1;
		for(int j=1,sum=f[i-1][0];j<=n;j++)
		{
			if(s[i][j]=='0')
			{
				p=j;
				break;
			}
			if(i>1&&s[i-1][j]!='1')
			{
				f[i][j]=(long long)sum*max(0,
				(f0[j]?f0[j]:i-1)-f1[j])%mod;
			}
			sum=(f[i-1][j]+(long long)sum*
			max(0,(f0[j]?f0[j]:i)-f1[j]))%mod;
		}
		for(int j=0,sum=0;j<=n;j++)
		{
			sum=sum*(s[i][j]!='1')+(j<p);
			f[i][j]=(f[i][j]+(long long)f[i-1][j]*sum)%mod;
		}
		for(int j=1;j<=n;j++)
		{
			f0[j]=(!f0[j]&&s[i][j]=='0')?i:f0[j];
			f1[j]=(s[i][j]=='1')?i:f1[j];
		}
	}
	int ans=0;
	for(int i=n,v=1;v&&i>=0;i--)
	{
		ans=(ans+(long long)f[n][i]*v)%mod;
		v=(long long)v*max(0,(f0[i]?f0[i]:n+1)-f1[i])%mod;
	}
	cout<<ans<<endl;
	return 0;
}