#include<bits/stdc++.h>
using namespace std;
int w,h;
char a[21][21];
bool f[25][25];
int fx[4]={0,1,0,-1};
int fy[4]={1,0,-1,0};
int ans;
void dfs(int x,int y){
	ans++;
	f[x][y]=true;
	for(int i=0;i<=3;i++){
		int tx=x+fx[i];
		int ty=y+fy[i];
		if(tx>0&&tx<=h&&ty>0&&ty<=w&&a[tx][ty]=='.'&&f[tx][ty]==false){
			dfs(tx,ty);
	    }
	}
}
int main(){
	cin>>w>>h;
	for(int i=1;i<=h;i++){
		for(int j=1;j<=w;j++){
			cin>>a[i][j];
		}
	}
    for(int i=1;i<=h;i++){
		for(int j=1;j<=w;j++){
			if(a[i][j]=='@'&&f[i][j]==false){
				dfs(i,j);
			}
		}
	}
	cout<<ans;
    return 0;
}

/**************************************************************
	Problem: 1897
	User: zengdongxin
	Language: C++
	Result: Accepted
	Time:37 ms
	Memory:2076 kb
****************************************************************/