#include<bits/stdc++.h>
using namespace std;
int n,m,ans=0;
char a[505][505];
int fx[4]={0,1,0,-1 };
int fy[4]={1,0,-1,0};
void dfs(int x,int y){
	for(int i=0;i<=3;i++){
		int tx=x+fx[i];
		int ty=y+fy[i];
		if(tx>=1&&tx<=n&&ty>=1&&ty<=m&&a[tx][ty]=='0'){
			a[tx][ty]='*';
			dfs(tx,ty);
		}
	}	
	
}

int main(){

	cin>>n>>m;
	
	for(int i=1;i<=n;i++){
		for(int j=1;j<=m;j++){
			cin>>a[i][j];
		}	
	}
	
	for(int i=1;i<=n;i++){
		for(int j=1;j<=m;j++){
			if((i==1||i==n||j==1||j==m)&&a[i][j]=='0'){
				a[i][j]='*';
				dfs(i,j);
				
			}
		}
	}
	
	for(int i=1;i<=n;i++){
		for(int j=1;j<=m;j++){
			if(a[i][j]=='0')	ans++;
		}
	}
	
	cout<<ans;
	
	return 0;
} 
/**************************************************************
	Problem: 1913
	User: hongjiaxu
	Language: C++
	Result: Accepted
	Time:41 ms
	Memory:2324 kb
****************************************************************/