#include <bits/stdc++.h>
using namespace std;
char c[1005][1005];
int x[1005],y[1005];
int main() {
ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
int n,m;
cin >> n >> m;
int l = 0;
for (int i=1;i<=n;++i) {
for (int j=1;j<=m;++j) {
cin >> c[i][j];
if (c[i][j] == '#') x[++l] = i,y[l] = j;
}
}
int ans = 0;
for (int i=1;i<=l;++i) {
c[x[i]][y[i]] = '.';
int cnt = 0;
for (int i=1;i<=n;++i) {
for (int j=1;j<=m;++j) {
if (c[i][j] == '.') {
if (c[i + 1][j] != '#' && c[i][j + 1] != '#' && c[i - 1][j] != '#' && c[i][j - 1] != '#'){
++cnt;
}
}
}
}
ans = max(ans,cnt);
c[x[i]][y[i]] = '#';
}
cout << ans;
return 0;
}
调了必关