邪门的测试

代码：

#include <iostream>
using namespace std;

const int N = 1005;
bool vis[N][N];
int dx[90] = {0, 0, 0, 1, 1, 1, -1, -1, -1};
int dy[90] = {0, 1, -1, 0, 1, -1, 0, 1, -1};
int n, m;
char arr[N][N];

int dfs(int i, int j)
{
    vis[i][j] = true;
    for (int ii = 1; ii <= 8; ii++)
    {
        int x = i + dx[ii], y = j + dy[ii];
        if (1 <= x && x <= n && 1 <= y && y <= m && arr[x][y] == 'W' && !vis[x][y])
        {
            vis[x][y] = true;
            dfs(x, y);
        }
    }
}

int main()
{
    cin >> n >> m;
    for (int i = 1; i <= n; i++)
    {
        for (int j = 1; j <= m; j++)
        {
            cin >> arr[i][j];
        }
    }

    int cnt = 0;
    for (int i = 1; i <= n; i++)
    {
        for (int j = 1; j <= m; j++)
        {
            if (!vis[i][j] && arr[i][j] == 'W')
            {
                dfs(i, j);
                cnt++;
            }
        }
    }
    cout << cnt << endl;
    return 0;
}