include [HTML_REMOVED]
include [HTML_REMOVED]
include [HTML_REMOVED]
include [HTML_REMOVED]
using namespace std;
const int N = 20;
bool arr[N];
int n;
void dfs(int start){
if(start > n){
for(int i=1;i<=n;i++){
if(arr[i]){
cout<[HTML_REMOVED]>n;
dfs(1);//从1开始搜索
return 0;
}