#include<stdio.h>
#include<string.h>
#include<queue>
#include<algorithm>
using namespace std;
struct P
{
    int x,y;
};
char s[25][25];
int y[8]={-1,0,1,-1,1,-1,0,1};
int x[8]={-1,-1,-1,0,0,1,1,1};
int a[4]={-1,0,0,1};
int b[4]={0,-1,1,0};
bool vis[25][25];
int r,c,X,Y;
int ans;
void bfs()
{
    queue<P>q;
    P p;
    p.x=X-1;
    p.y=Y-1;
    q.push(p);
    vis[p.x][p.y]=1;
    while(q.size())
    {
        P t=q.front(); //printf("%d %d\n",t.x,t.y);
        q.pop();
        for(int i=0;i<8;i++)
        {
            P v;
            v.x=t.x+x[i];
            v.y=t.y+y[i];
            if(v.x>=0&&v.x<r&&v.y>=0&&v.y<c&&s[v.x][v.y]=='X'&&vis[v.x][v.y]==0)
            {
                q.push(v);
                vis[v.x][v.y]=1;
            }
        }
        int sum=4;
        for(int i=0;i<4;i++)
        {
            int sx=t.x+a[i];
            int sy=t.y+b[i];
            if(sx>=0&&sx<r&&sy>=0&&sy<c&&s[sx][sy]=='X')
                sum--;
        } //printf("%d ",sum);
        ans+=sum;
    }
}

int main()
{
    while(scanf("%d %d %d %d",&r,&c,&X,&Y)!=EOF)
    {
        getchar();
        if(r==0&&c==0&&X==0&&Y==0) break;
        else
        {
            ans=0;
            memset(vis,0,sizeof(vis));
            memset(s,'\0',sizeof(s));
            for(int i=0;i<r;i++)
                scanf("%s",s[i]);
            bfs();
            printf("%d\n",ans);
        }
    }return 0;
}