luogu1706全排列

 #include<bits/stdc++.h>
 using namespace std;
 int a[+];
 bool b[+];
 int search(int k);
 int print();
 int n,num;
 int main(){
     cin>>n;
     search();
     cout<<num<<endl;
     return ;
 }
 int search(int k){
     for(int i=;i<=n;i++)
         if(!b[i]){
             a[k]=i;
             b[i]=;
             if(k==n) print();
             else search(k+);
             b[i]=;
         }

 }
 int print(){
     num++;
     for(int i=;i<=n;i++)
     cout<<setw()<<a[i];
     cout<<endl;
 }

啦啦啦，又来了一遍全排列