#include<bits/stdc++.h>
using namespace std;
int n,m,s;
char a[505][505];
int fx[4]={1,-1,0,0};
int fy[4]={0,0,1,-1};
void dfs(int x,int y){
    a[x][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'){
            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') dfs(i,j);
        }
    }
    for(int i=1;i<=n;i++){
        for(int j=1;j<=m;j++){
            if(a[i][j]=='0') s++;
        }
    }
    cout<<s;
    return 0;
}
/**************************************************************
	Problem: 1913
	User: linzihang
	Language: C++
	Result: Accepted
	Time:39 ms
	Memory:2324 kb
****************************************************************/