水题

#include <bits/stdc++.h>
using namespace std;
const int N = 1005;

int vis[N][N] = {0}, n, m;
char a[N][N];

int dx[8] = {-1, -1, -1, 0, 0, 1, 1, 1};

int dy[8] = {-1, 0, 1, -1, 1, -1, 0, 1};

void dfs(int x, int y) {
if (x > n || y > m || x < 1 || y < 1 || a[x][y] == '.')
return;

if (!vis[x][y]) {
	vis[x][y] = 1;
	for (int i = 0; i < 8; i++) {
		dfs(x + dx[i], y + dy[i]);
	}
}

}

int main() {
int tot = 0;
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 (a[i][j] == 'W' && !vis[i][j]) {
			dfs(i, j);
			tot++;
		}
	}
}

cout << tot << endl;
return 0;

}