#include<bits/stdc++.h>
using namespace std;
typedef pair<int,int> P;
queue<P> q;
int n,d[105][105],l,cx,cy,step[105][105];
char a[105][105];
void bfs()
{
	q.push(P(cx,cy)); 
	d[cx][cy]=1;
	while(!q.empty())
	{
		int x=q.front().first;
		int y=q.front().second;
		q.pop();
		if(a[x][y]=='B')
		{
			cout<<step[x][y]-1;
			l=1;
			break;
		}
		int i=1;
		while(1)
		{
			if(a[x+i][y]=='x'||d[x+i][y]==1||x+i>n)
			{
				break;
			}
			q.push(P(x+i,y));
			d[x+i][y]=1;
			step[x+i][y]=step[x][y]+1;
			i++;
		}
		i=1;
		while(1)
		{
			if(a[x-i][y]=='x'||d[x-i][y]==1||x-i<1)
			{
				break;
			}
			q.push(P(x-i,y));
			d[x-i][y]=1;
			step[x-i][y]=step[x][y]+1;
			i++;
		}
		i=1;
		while(1)
		{
			if(a[x][y+i]=='x'||d[x][y+i]==1||y+i>n)
			{
				break;
			}
			q.push(P(x,y+i));
			d[x][y+i]=1;
			step[x][y+i]=step[x][y]+1;
			i++;
		}
		i=1;
		while(1)
		{
			if(a[x][y-i]=='x'||d[x][y-i]==1||y-i<1)
			{
				break;
			}
			q.push(P(x,y-i));
			d[x][y-i]=1;
			step[x][y-i]=step[x][y]+1;
			i++;
		}
	}
}
int main()
{
	cin>>n;
	for(int i=1;i<=n;i++)
	{
		for(int j=1;j<=n;j++)
		{
			cin>>a[i][j];
			if(a[i][j]=='A')
			{
				cx=i;
				cy=j;
			}
		}
	}
	bfs();
	if(l==0)
	{
		cout<<-1;
	}
}