代码发崩了，再发一次
```cpp
#include<cstdio>
int n,m,s;
char a[1001][1001];
bool count(int x,int y) {
int cc=1;
if(a[x][y+1]=='#')cc++;
if(a[x+1][y]=='#')cc++;
if(a[x+1][y+1]=='#')cc++;
if(cc==3)return false;
return true;
}
void dfs(int x,int y){
a[x][y]='.';
if(a[x-1][y]=='#')dfs(x-1,y);
if(a[x+1][y]=='#')dfs(x+1,y);
if(a[x][y-1]=='#')dfs(x,y-1);
if(a[x][y+1]=='#')dfs(x,y+1);
}
int main(){
scanf("%d%d\n",&n,&m);
for(int i=1;i<=n;i++){
for(int j=1;j<=m;j++)scanf("%c",&a[i][j]);
scanf("\n");
}
for(int i=1;i<n;i++){
for(int j=1;j<m;j++){
if(a[i][j]=='#'&&!count(i,j)){
printf("Bad placement.");
return 0;
}
}
}
for(int i=1;i<=n;i++){
for(int j=1;j<=m;j++){
if(a[i][j]=='#'){
dfs(i,j);
s++;
}
}
}
printf("There are %d ships.",s);
}
```
```cpp
#include<cstdio>
#include<queue>
using namespace std;
char a[1001][1001],aa[1001][1001];
int r,c,s,flag;
queue<int>bf;
int get() {
int xx=bf.front();
bf.pop();
return xx;
}
bool count(int x,int y) {
int cc=1;
if(aa[x][y+1]=='#')cc++;
if(aa[x+1][y]=='#')cc++;
if(aa[x+1][y+1]=='#')cc++;
if(cc==3)return false;
return true;
}
void bfs(int y,int x) {
if(flag==1)return;
if(!count(x,y)) {
flag=1;
return;
}
if(a[x+1][y]=='#') {
a[x+1][y]='.';
bf.push(x+1);
bf.push(y);
}
if(a[x][y+1]=='#') {
a[x][y+1]='.';
bf.push(x);
bf.push(y+1);
}
if(a[x-1][y]=='#') {
a[x-1][y]='.';
bf.push(x-1);
bf.push(y);
}
if(a[x][y-1]=='#') {
a[x][y-1]='.';
bf.push(x);
bf.push(y-1);
}
if(bf.empty())return;
bfs(get(),get());
}
int main() {
scanf("%d%d\n",&r,&c);
for(int i=1; i<=r; i++) {
for(int j=1; j<=c; j++) {
scanf("%c",&a[i][j]);
aa[i][j]=a[i][j];
}
scanf("\n");
}
for(int i=1; i<=r; i++) {
for(int j=1; j<=c; j++) {
if(flag==1) {
printf("Bad placement.");
return 0;
}
if(a[i][j]=='#') {
bfs(j,i);
s++;
}
}
}
printf("There are %d ships.",s);
}
```
by TinyKiecoo @ 2018-11-03 17:42:45
wo ye shi
by luoxiao233 @ 2018-12-04 09:14:17
特判
by Memory_L_Exceeded @ 2021-10-16 19:46:40