#include <iostream>
#include <cstring>
using namespace std;
const int maxn = 105;
char s[maxn][maxn];
int x1,y1,x2,y2,n,ans = 65535;
bool vis[maxn][maxn];
int dx[] = {0,0,1,-1};
int dy[] = {1,-1,0,0};
void solve(int x,int y,int ob,int j){
	if((x>n||x<1)||(y>n||y<1)||s[x][y] == 'x'||vis[x][y])	return;
	if(ob > ans)	return;
	if(x == x2 && y == y2){
		ans = min(ans,ob);
		return;
	}
	vis[x][y] = true;
	for(int i=0;i<4;i++){
		int nx = x + dx[i],ny = y + dy[i];
		if(j == 0){
			solve(nx,ny,ob,i+1);
		}
		else{
			if(i+1 == j){
				solve(nx,ny,ob,i+1);
			}
			else{
				solve(nx,ny,ob+1,i+1);
			}
		}
	}
	vis[x][y] = false;
}
int main()
{
	cin>>n;
	for(int i=1;i<=n;i++){
		for(int j=1;j<=n;j++){
			cin>>s[i][j];
			if(s[i][j] == 'A'){
				x1 = i;
				y1 = j;
			}
			else if(s[i][j] == 'B'){
				x2 = i;
				y2 = j;
			}
		}
	}
	memset(vis,false,sizeof(vis));
	solve(x1,y1,0,0);
	if(ans != 65535) cout<<ans;
	else cout<<"-1";
	return 0;
 }