#include <iostream>

using namespace std;

int a[1005][1005], m, n, cnt = 0;
int dx[4] = {0, 0, 1, -1};
int dy[4] = {-1, 1, 0, 0};

void dfs(int x, int y)
{
	a[x][y] = 0;
	for(int i = 0; i < 4; i++)
	{
		int tx = x + dx[i];
		int ty = y + dy[i];
		if(tx > 0 && tx <= m && ty > 0 && ty <=n && a[tx][ty])
		{
			//a[tx][ty] = 0;
			dfs(tx, ty);
		}
	}
}

bool d(int i,int j)
{
	int c = 0;
	if(a[i][j])  c++;
	if(a[i+1][j])  c++;
	if(a[i][j+1])  c++;
	if(a[i+1][j+1])  c++;
	if(c == 3)  return 0;
	return 1;
}

int main()
{
	cin >> m >> n;
	char ch;
	getchar();
	for(int i = 1; i <= m; i++)
	{
		for(int j = 1; j <= n; j++)
		{
			ch = getchar();
			if(ch == '.')
			{
				a[i][j] = 0;
			}
			else
			{
				a[i][j] = 1;
			}
		}
		getchar();
	}
	for(int i = 1; i <= m; i++)
	{
		for(int j = 1; j <= n; j++)
		{
			if(i < m && j < n && !d(i, j))
			{
				cout << "Bad placement.";
				return 0;
			}
		}
	}
	for(int i = 1; i <= m; i++)
	{
		for(int j = 1; j <= n; j++)
		{
			if(a[i][j])
			{
//				a[i][j] = 0;
				dfs(i, j);
				cnt++;
			}
		}
	}
	cout << "There are " << cnt << " ships.";
	return 0;
 } 

帮忙看一下呗~~