#include<cstdio>
#define syy myson
using namespace std;
int n,m,p[104][14],pic[104][14],anss,ans=0,i,j,k,l;
void put(int x,int y)
{
	pic[x][y]=1;
	if(x-1>0)pic[x-1][y]=1;
	if(x-2>0)pic[x-2][y]=1;
	if(y-1>0)pic[x][y-1]=1;
	if(y-2>0)pic[x][y-2]=1;
	if(x+1<=n)pic[x+1][y]=1;
	if(x+2<=n)pic[x+2][y]=1;
	if(y+1<=m)pic[x][y+1]=1;
	if(y+2<=m)pic[x][y+2]=1;
	anss++;
}
int Main()
{
	freopen("cannon.in","r",stdin);freopen("cannon.out","w",stdout);
	scanf("%d%d",&n,&m);
	for(i=1;i<=n;i++)
	{
		char fuck[11];
		scanf("%s",&fuck);
		for(j=1;j<=m;j++)
		{
			if(fuck[j-1]=='P')p[i][j]=0;
			else p[i][j]=1;
		}
	}
	/*
	for(i=1;i<=n;i++)
	{
		printf("\n");
		for(j=1;j<=m;j++)printf("%d ",p[i][j]);
	}
	*/
	for(i=1;i<=n;i++)for(j=1;j<=m;j++)if(!p[i][j])
	{
		anss=0;
		for(k=1;k<=n;k++)for(l=1;l<=m;l++)pic[k][l]=p[k][l];
		put(i,j);
		for(k=1;k<=n;k++)for(l=1;l<=m;l++)if(!pic[k][l])put(k,l);
		//printf("%d ",anss);
		if(anss>ans)ans=anss;
	}
	printf("%d",ans);
	return 0;
}
int main(){;}
int syy=Main();