#include <cstdio>
#include <cstring>
#include <iostream>
#include <string>
#include <cmath>
#include <bitset>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <deque>
#include <algorithm>
#include <complex>
#include <unordered_map>
#include <unordered_set>
#include <random>
#include <cassert>
#include <fstream>
#include <utility>
#include <functional>
#include <time.h>
#include <stack>
#include <array>
#define popcount __builtin_popcount
using namespace std;
typedef long long int ll;
typedef pair<int, int> P;
int n, m;
string a[1010];
int b[1010][1010];
int c;
int dx[8]={1, -1, 0, 0, 1, 1, -1, -1}, dy[8]={0, 0, 1, -1, 1, -1, 1, -1};
void dfs(int x, int y, int v){
	b[x][y]=v;
	for(int k=0; k<4; k++){
		int x1=x+dx[k], y1=y+dy[k];
		if(x1<0 || x1>=n || y1<0 || y1>=m) continue;
		if(a[x1][y1]=='x' || b[x1][y1]>=0) continue;
		dfs(x1, y1, v);
	}
}
void dfs2(int x, int y, int v, int &cnt){
	cnt++;
	b[x][y]=v;
	for(int k=0; k<8; k++){
		int x1=x+dx[k], y1=y+dy[k];
		if(x1<0 || x1>=n || y1<0 || y1>=m) continue;
		if(b[x1][y1]>=0) continue;
		if(a[x1][y1]=='.'){
			if(k<4) dfs(x1, y1, v);
		}else dfs2(x1, y1, v, cnt);
	}
}
int cnt[1000010];
vector<vector<int>> g;
int dp[2][1000010];
void dfs3(int x, int p){
	for(auto y:g[x]){
		if(y==p) continue;
		dfs3(y, x);
		dp[1][x]+=dp[0][y];
		dp[0][x]+=max(dp[0][y], dp[1][y]);
	}
	dp[1][x]+=cnt[x];
}
int main()
{
	cin>>n>>m;
	for(int i=0; i<n+2; i++){
		for(int j=0; j<m+2; j++) a[i]+='.', b[i][j]=-1;
	}
	for(int i=1; i<=n; i++){
		string s; cin>>s;
		for(int j=1; j<=m; j++) a[i][j]=s[j-1];
	}
	n+=2, m+=2;
	dfs(0, 0, 0);
	c++;
	for(int i=0; i<n; i++){
		for(int j=0; j<m; j++){
			if(b[i][j]==-1 && a[i][j]=='x'){
				dfs2(i, j, c, cnt[c]);
				c++;
			}
		}
	}
	g.resize(c);
	for(int i=0; i<n; i++){
		for(int j=0; j<m; j++){
			if(j<m-1 && b[i][j]!=b[i][j+1]){
				g[b[i][j]].push_back(b[i][j+1]);
				g[b[i][j+1]].push_back(b[i][j]);
			}
			if(i<n-1 && b[i][j]!=b[i+1][j]){
				g[b[i][j]].push_back(b[i+1][j]);
				g[b[i+1][j]].push_back(b[i][j]);
			}
		}
	}
	for(int i=0; i<c; i++){
		sort(g[i].begin(), g[i].end());
		g[i].erase(unique(g[i].begin(), g[i].end()), g[i].end());
	}
	dfs3(0, -1);
	cout<<max(dp[0][0], dp[1][0])<<endl;
	return 0;
}