#include<iostream>
#include<string.h>
#include<queue>
using namespace std;
struct id
{
	int x,y,s;
};
queue<id>q;
int n,m,x,y,sx,sy,ans,k;
int xx[8]={-1,-1,-1,0,0,1,1,1};
int yy[8]={-1,0,1,-1,1,-1,0,1};
bool qp[110][110];
char ch;
int main()
{
	memset(qp,false,sizeof(qp));
	cin>>m>>n>>x>>y;
	for(int i=1;i<=n;i++)
	{
		for(int j=1;j<=m;j++)
		{
			cin>>ch;
			if(ch=='.')qp[i][j]=true;
		}
	}
	sy=x;
	sx=n-y+1;
	q.push(id{sx,sy,0});
	qp[sx][sy]=false;
	while(!q.empty())
	{
		int tx=q.front().x;
		int ty=q.front().y;
		ans=q.front().s;
		q.pop();
		for(int i=0;i<8;i++)
		{
			int nx=tx+xx[i];
			int ny=ty+yy[i];
			if(qp[nx][ny])
			{
				q.push(id{nx,ny,ans+1});
				qp[nx][ny]=false;
			}
		}
	}
	cout<<ans;
	return 0;
}

#include<bits/stdc++.h>
using namespace std;
#define int long long
const int N=105;
int n,m;
int a[N][N],dis[N][N];
int dx[]={-1,-1,-1,0,0,1,1,1};
int dy[]={-1,0,1,-1,1,-1,0,1};
queue<pair<int,int> > que;
bool inside(int nx,int ny){
    return nx>=1&&nx<=n&&ny>=1&&ny<=m;
}
void bfs(int sr,int sc){
    memset(dis,0x3f,sizeof(dis));
    dis[sr][sc]=0;
    que.push({sr,sc});
    while(!que.empty()){
        int x=que.front().first;
        int y=que.front().second;
        que.pop();
        for(int i=0;i<8;i++){
            int nx=x+dx[i];
            int ny=y+dy[i];
            if(!inside(nx,ny)){
			    continue;
			}
            if(a[nx][ny]=='*'){
			    continue;
			}
            if(dis[x][y]+1<dis[nx][ny]){
                dis[nx][ny]=dis[x][y]+1;
                que.push({nx,ny});
            }
        }
    }
}
signed main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int Y,X,Mx,My;
    cin>>Y>>X>>Mx>>My;
    n=X;
	m=Y;
    int sr=X-My+1;
    int sc=Mx;
    for(int i=1;i<=X;i++){
        string s;
        cin>>s;
        for(int j=1;j<=Y;j++){
            a[i][j]=s[j-1];
        }
    }
    bfs(sr,sc);
    int ret=0;
    for(int i=1;i<=n;i++){
        for(int j=1;j<=m;j++){
            if(a[i][j]=='.'){
                ret=max(ret, dis[i][j]);
            }
        }
    }
    cout<<ret<<endl;
    return 0;
}
//包AC的

#include<iostream>
#include<string.h>
#include<queue>
using namespace std;
struct id
{
int x,y,s;
};
queue<id>q;
int n,m,x,y,sx,sy,ans,k;
int xx[8]={-1,-1,-1,0,0,1,1,1};
int yy[8]={-1,0,1,-1,1,-1,0,1};
bool qp[110][110];
char ch;
int main()
{
memset(qp,false,sizeof(qp));
cin>>m>>n>>x>>y;
for(int i=1;i<=n;i++)
{
for(int j=1;j<=m;j++)
{
cin>>ch;
if(ch=='.')qp[i][j]=true;
}
}
sy=x;
sx=n-y+1;
q.push(id{sx,sy,0});
qp[sx][sy]=false;
while(!q.empty())
{
int tx=q.front().x;
int ty=q.front().y;
ans=q.front().s;
q.pop();
for(int i=0;i<8;i++)
{
int nx=tx+xx[i];
int ny=ty+yy[i];
if(qp[nx][ny])
{
q.push(id{nx,ny,ans+1});
qp[nx][ny]=false;
}
}
}
cout<<ans;
return 0;
}