我应该是第一个发题解的吧！！吼吼！ 入门深搜题，注释全部都在代码里 坑的地方就在输出的最后不能有空格，要进行判断

dfs: #include<bits/stdc++.h> using namespace std; int n,a[100],zip[100]; 哈哈抄不了！！

#include<bits/stdc++.h> using namespace std; typedef int j; j n,a[100],vis[100]; j f(j p){ if(p==n+1){ for(j i=1;i<=n;i++){ cout<<a[i]<<" "; } cout<<endl; } for(j i=1;i<=n;i++){ if(vis[i]==0){ vis[i]=1; a[p]=i; f(p+1); vis[i]=0; } } } j main(){ cin>>n; f(1); return 0; }

#include <bits/stdc++.h> using namespace std; int a[15],n; bool vis[15]; void dfs(int t) { if(t>n){ for(int i=1;i<=n;i++) cout<<a[i]<<" "; cout<<endl; return; } for(int i=1;i<=n;i++){ if(vis[i]==false){ vis[i]=true; a[t]=i; dfs(t+1); vis[i]=false; } } } int main(){ cin>>n; dfs(1); return 0; }

可以用next_permutation函数来遍历全排序 代码： #include <bits/stdc++.h> using namespace std; int main(){ int n,a[13]; cin>>n; for(int i=1;i<=n;i++){ a[i]=i; } sort(a+1,a+n+1); do{ for(int i=1;i<=n;i++)cout<<a[i]<<' '; cout<<endl; }while(next_permutation(a+1,a+n+1)); return 0; }

>

#include<bits/stdc++.h> using namespace std; int main() { int n; cin>>n; if(n1){ cout<<"1 "<<endl; } else if(n2){ cout<<"1 2 "<<endl; cout<<"2 1 "<<endl; } else if(n3){ cout<<"1 2 3 "<<endl; cout<<"1 3 2 "<<endl; cout<<"2 1 3 "<<endl; cout<<"2 3 1 "<<endl; cout<<"3 1 2 "<<endl; cout<<"3 2 1 "<<endl; } else if(n4){ cout<<"1 2 3 4 "<<endl; cout<<"1 2 4 3 "<<endl; cout<<"1 3 2 4 "<<endl; cout<<"1 3 4 2 "<<endl; cout<<"1 4 2 3 "<<endl; cout<<"1 4 3 2 "<<endl; cout<<"2 1 3 4 "<<endl; cout<<"2 1 4 3 "<<endl; cout<<"2 3 1 4 "<<endl; cout<<"2 3 4 1 "<<endl; cout<<"2 4 1 3 "<<endl; cout<<"2 4 3 1 "<<endl; cout<<"3 1 2 4 "<<endl; cout<<"3 1 4 2 "<<endl; cout<<"3 2 1 4 "<<endl; cout<<"3 2 4 1 "<<endl; cout<<"3 4 1 2 "<<endl; cout<<"3 4 2 1 "<<endl; cout<<"4 1 2 3 "<<endl; cout<<"4 1 3 2 "<<endl; cout<<"4 2 1 3 "<<endl; cout<<"4 2 3 1 "<<endl; cout<<"4 3 1 2 "<<endl; cout<<"4 3 2 1 "<<endl; } else if(n==5){ cout<<"1 2 3 4 5 "<<endl; cout<<"1 2 3 5 4 "<<endl; cout<<"1 2 4 3 5 "<<endl; cout<<"1 2 4 5 3 "<<endl; cout<<"1 2 5 3 4 "<<endl; cout<<"1 2 5 4 3 "<<endl; cout<<"1 3 2 4 5 "<<endl; cout<<"1 3 2 5 4 "<<endl; cout<<"1 3 4 2 5 "<<endl; cout<<"1 3 4 5 2 "<<endl; cout<<"1 3 5 2 4 "<<endl; cout<<"1 3 5 4 2 "<<endl; cout<<"1 4 2 3 5 "<<endl; cout<<"1 4 2 5 3 "<<endl; cout<<"1 4 3 2 5 "<<endl; cout<<"1 4 3 5 2 "<<endl; cout<<"1 4 5 2 3 "<<endl; cout<<"1 4 5 3 2 "<<endl; cout<<"1 5 2 3 4 "<<endl; cout<<"1 5 2 4 3 "<<endl; cout<<"1 5 3 2 4 "<<endl; cout<<"1 5 3 4 2 "<<endl; cout<<"1 5 4 2 3 "<<endl; cout<<"1 5 4 3 2 "<<endl; cout<<"2 1 3 4 5 "<<endl; cout<<"2 1 3 5 4 "<<endl; cout<<"2 1 4 3 5 "<<endl; cout<<"2 1 4 5 3 "<<endl; cout<<"2 1 5 3 4 "<<endl; cout<<"2 1 5 4 3 "<<endl; cout<<"2 3 1 4 5 "<<endl; cout<<"2 3 1 5 4 "<<endl; cout<<"2 3 4 1 5 "<<endl; cout<<"2 3 4 5 1 "<<endl; cout<<"2 3 5 1 4 "<<endl; cout<<"2 3 5 4 1 "<<endl; cout<<"2 4 1 3 5 "<<endl; cout<<"2 4 1 5 3 "<<endl; cout<<"2 4 3 1 5 "<<endl; cout<<"2 4 3 5 1 "<<endl; cout<<"2 4 5 1 3 "<<endl; cout<<"2 4 5 3 1 "<<endl; cout<<"2 5 1 3 4 "<<endl; cout<<"2 5 1 4 3 "<<endl; cout<<"2 5 3 1 4 "<<endl; cout<<"2 5 3 4 1 "<<endl; cout<<"2 5 4 1 3 "<<endl; cout<<"2 5 4 3 1 "<<endl; cout<<"3 1 2 4 5 "<<endl; cout<<"3 1 2 5 4 "<<endl; cout<<"3 1 4 2 5 "<<endl; cout<<"3 1 4 5 2 "<<endl; cout<<"3 1 5 2 4 "<<endl; cout<<"3 1 5 4 2 "<<endl; cout<<"3 2 1 4 5 "<<endl; cout<<"3 2 1 5 4 "<<endl; cout<<"3 2 4 1 5 "<<endl; cout<<"3 2 4 5 1 "<<endl; cout<<"3 2 5 1 4 "<<endl; cout<<"3 2 5 4 1 "<<endl; cout<<"3 4 1 2 5 "<<endl; cout<<"3 4 1 5 2 "<<endl; cout<<"3 4 2 1 5 "<<endl; cout<<"3 4 2 5 1 "<<endl; cout<<"3 4 5 1 2 "<<endl; cout<<"3 4 5 2 1 "<<endl; cout<<"3 5 1 2 4 "<<endl; cout<<"3 5 1 4 2 "<<endl; cout<<"3 5 2 1 4 "<<endl; cout<<"3 5 2 4 1 "<<endl; cout<<"3 5 4 1 2 "<<endl; cout<<"3 5 4 2 1 "<<endl; cout<<"4 1 2 3 5 "<<endl; cout<<"4 1 2 5 3 "<<endl; cout<<"4 1 3 2 5 "<<endl; cout<<"4 1 3 5 2 "<<endl; cout<<"4 1 5 2 3 "<<endl; cout<<"4 1 5 3 2 "<<endl; cout<<"4 2 1 3 5 "<<endl; cout<<"4 2 1 5 3 "<<endl; cout<<"4 2 3 1 5 "<<endl; cout<<"4 2 3 5 1 "<<endl; cout<<"4 2 5 1 3 "<<endl; cout<<"4 2 5 3 1 "<<endl; cout<<"4 3 1 2 5 "<<endl; cout<<"4 3 1 5 2 "<<endl; cout<<"4 3 2 1 5 "<<endl; cout<<"4 3 2 5 1 "<<endl; cout<<"4 3 5 1 2 "<<endl; cout<<"4 3 5 2 1 "<<endl; cout<<"4 5 1 2 3 "<<endl; cout<<"4 5 1 3 2 "<<endl; cout<<"4 5 2 1 3 "<<endl; cout<<"4 5 2 3 1 "<<endl; cout<<"4 5 3 1 2 "<<endl; cout<<"4 5 3 2 1 "<<endl; cout<<"5 1 2 3 4 "<<endl; cout<<"5 1 2 4 3 "<<endl; cout<<"5 1 3 2 4 "<<endl; cout<<"5 1 3 4 2 "<<endl; cout<<"5 1 4 2 3 "<<endl; cout<<"5 1 4 3 2 "<<endl; cout<<"5 2 1 3 4 "<<endl; cout<<"5 2 1 4 3 "<<endl; cout<<"5 2 3 1 4 "<<endl; cout<<"5 2 3 4 1 "<<endl; cout<<"5 2 4 1 3 "<<endl; cout<<"5 2 4 3 1 "<<endl; cout<<"5 3 1 2 4 "<<endl; cout<<"5 3 1 4 2 "<<endl; cout<<"5 3 2 1 4 "<<endl; cout<<"5 3 2 4 1 "<<endl; cout<<"5 3 4 1 2 "<<endl; cout<<"5 3 4 2 1 "<<endl; cout<<"5 4 1 2 3 "<<endl; cout<<"5 4 1 3 2 "<<endl; cout<<"5 4 2 1 3 "<<endl; cout<<"5 4 2 3 1 "<<endl; cout<<"5 4 3 1 2 "<<endl; cout<<"5 4 3 2 1 "<<endl; } }