include<bits/stdc++.h>

define ulli unsigned long long int

define ll long long

define f first

define se second

define endl "\n"

define maxn 1000006

using namespace std; const int MOD = 1e9+7; const int tnh = 1008;

ll dx[4] = {-1,0,0,1}; ll dy[4] = {0,1,-1,0}; ll n,m; char a[1008][1008]; pair<ll,ll> na,nb; bool found = false; map f; void bfs(ll x,ll y) { queuebase::syncwith_stdio(false); cin.tie(NULL); cout.tie(NULL); cin>>n>>m; for(ll i = 1;i <= n;i++) { for(ll j = 1;j <= m;j++) { cin>>a[i][j]; if(a[i][j] == 'A') na = {i,j}; if(a[i][j] == 'B') nb = {i,j}; } } f[na] = 1; bfs(na.f,na.se); cout<<f[nb];

return 0;

}