我的代码：

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;

const char c = '#';
int n, m;
char s[1001][1001];
int ans;

int main() {
	scanf("%d%d", &n, &m);
	for (int i = 1; i <= n; i++)
		scanf("%s", s[i] + 1);
	for (int i = 1; i <= n; i++)
		for (int j = 1; i <= m; i++)
			if (s[i][j] == c) {
				ans++;
				if (s[i + 1][j] == c)
					s[i + 1][j] = 'a';
				if (s[i - 1][j] == c)
					s[i - 1][j] = 'a';
				if (s[i][j + 1] == c)
					s[i][j + 1] = 'a';
				if (s[i][j - 1] == c)
					s[i][j - 1] = 'a';
				if (s[i + 1][j + 1] == c)
					s[i + 1][j + 1] = 'a';
				if (s[i - 1][j - 1] == c)
					s[i - 1][j - 1] = 'a';
				if (s[i + 1][j - 1] == c)
					s[i + 1][j - 1] = 'a';
				if (s[i - 1][j + 1] == c)
					s[i - 1][j + 1] = 'a';
			} else {
				if (s[i][j] == 'a') {
					if (s[i + 1][j] == 'a')
						s[i + 1][j] = 'a';
					if (s[i - 1][j] == 'a')
						s[i - 1][j] = 'a';
					if (s[i][j + 1] == 'a')
						s[i][j + 1] = 'a';
					if (s[i][j - 1] == 'a')
						s[i][j - 1] = 'a';
					if (s[i + 1][j + 1] == 'a')
						s[i + 1][j + 1] = 'a';
					if (s[i - 1][j - 1] == 'a')
						s[i - 1][j - 1] = 'a';
					if (s[i + 1][j - 1] == 'a')
						s[i + 1][j - 1] = 'a';
					if (s[i - 1][j + 1] == 'a')
						s[i - 1][j + 1] = 'a';
				}
			}
	printf("%d\n", ans);
}