题解 | 数水坑

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

int n, m;
char str[110][110];
int cnt;
int dx[] = {-1, -1, 0, 1, 1, 1, 0, -1};
int dy[] = {0, 1, 1, 1, 0, -1, -1, -1};

void dfs(int x, int y) {
	str[x][y] = '.';
	for (int i = 0; i < 8; i++) {
		int tx = dx[i] + x;
		int ty = dy[i] + y;
		if (tx >= 1 && ty >= 1 && tx <= n && ty <= m && str[tx][ty] == 'W') {
			dfs(tx, ty);
		}
	}
}

int main() {
	cin >> n >> m;
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= m; j++) {
			cin >> str[i][j];
		}
	}
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= m; j++) {
			if (str[i][j] == 'W') {
				cnt++;
				dfs(i, j);
			}
		}
	}
	cout << cnt;
	return 0;
}