#include<iostream>
#include<cstdio>
#include<cmath>
#include<string>
#include<algorithm>
#include<cstdlib>

using namespace std;

int n,a[11][11],sum=0;
int x[8]={1,1,0,-1,-1,-1,0,1},y[8]={0,-1,-1,-1,0,1,1,1};

void putin()
{
	cin>>n;
	for(int i=1;i<=n;++i)
		for(int j=1;j<=n;++j)
			cin>>a[i][j];
}
void se(int xl,int yl)
{
	a[xl][yl]=1;
	for(int i=0;i<=7;++i)
	{
		int xx,yy;
		xx=xl+x[i];yy=yl+y[i];
		if(xx>0&&xx<=n&&yy>0&&yy<=n&&!a[xx][yy])
		{
			if(xx==1&&yy==n)
				sum++;
			else
				se(xx,yy);
			a[xx][yy]=0;
		}
	}
}

int main()
{
	putin();
	se(1,1);
	cout<<sum;
	return 0;
}
/**************************************************************
	Problem: 2114
	User: admin
	Language: C++
	Result: Accepted
	Time:37 ms
	Memory:2072 kb
****************************************************************/