#include<bits/stdc++.h>
using namespace std;
int n,m,ans;
char a[501][501];
int tx[4]={1,-1,0,0};
int ty[4]={0,0,-1,1};
void dfs(int x,int y)
{
    a[x][y]='*';
    for(int i=0;i<=3;i++)
    {
        int fx=x+tx[i];
        int fy=y+ty[i];
        if(fx>=1&&fx<=n&&fy>=1&&fy<=m&&a[fx][fy]=='0') dfs(fx,fy);
    }
}
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') 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;
}
/**************************************************************
	Problem: 1913
	User: caijiajie
	Language: C++
	Result: Accepted
	Time:25 ms
	Memory:2320 kb
****************************************************************/