#include <bits/stdc++.h>
#define rep(i,x,y)  for(int i=x;i<=y;i++)
#define rep1(i,x,y) for(int i=x;i<y;i++)
#define per(i,x,y)  for(int i=y;i>=x;i--)
#define IOS ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define _mset(s,_) memset(s,_,sizeof(s));
using namespace std;
int w,h,sx,sy,step;
char a[25][25];
bool vis[25][25];
inline int read(){
	int x=0,f=1;
	char ch=getchar();
	while(ch<'0'||ch>'9'){
		if(ch=='-')
		f=-1;
		ch=getchar();
	}
	while(ch>='0'&&ch<='9'){
		x=(x<<1)+(x<<3)+(ch^48);
		ch=getchar();
	}
	return x*f;
}
void dfs(int x,int y){
	if(x<1||y<1||x>h||y>w||vis[x][y]!=0||a[x][y]=='#') return ;
	vis[x][y]=1;
	step++;
	dfs(x-1,y);
	dfs(x,y-1);
	dfs(x+1,y);
	dfs(x,y+1);
 }

int main()
{
   IOS
//   cin>>w>>h;
   w=read();
   h=read();
   rep(i,1,h){
   	rep(j,1,w){
		cin>>a[i][j];
		if(a[i][j]=='@'){
			sx=i;sy=j;
		}	
	   }
   }
   dfs(sx,sy);
   cout<<step;
   return 0;
}