为啥RE了好多点呢？求助！！！

#include <bits/stdc++.h>
using namespace std;
int r,c;
char mp[1010][1010];
int dx[4]={0,-1,1,0};
int dy[4]={-1,0,0,1};
int dfs(int x,int y)
{
	mp[x][y]='*';
	for (int i=0;i<4;i++)
		if (x+dx[i]>0 && x+dx[i]<=r && y+dy[i]>0 && y+dy[i]<=c)
			if (mp[x+dx[i]][y+dy[i]]=='#')
				dfs(x+dx[i],y+dy[i]);
}
bool okk (int i,int j)
{
	int k=0;
	if (mp[i][j]=='#') k++;
	if (mp[i+1][j]=='#') k++;
	if (mp[i][j+1]=='#') k++;
	if (mp[i+1][j+1]=='#') k++;
	if (k==3) return false;
	return true;
}
int main()
{
	scanf("%d%d",&r,&c);
	for (int i=1;i<=r;i++)
		for (int j=1;j<=c;j++)
			cin>>mp[i][j];
	int ans=0;
	for (int i=1;i<r;i++)
		for (int j=1;j<c;j++)
			if (okk(i,j)==false){
				printf("Bad placement.");
				return 0;
			}
	for (int i=1;i<=r;i++)
		for (int j=1;j<=c;j++)
			if (mp[i][j]=='#') {
				dfs(i,j);	
				ans++;
			}
	printf("There are %d ships.",ans);
	return 0;
}