求1到n的全排列（搜索入门）

#include<iostream>#include<cstdio>using namespace std;#define N 1009int use[N];int num[N];void dfs(int n,int t){           //t:num[]中准备存放的第t-1个数    if(t==n){for(int i=0;i<n;i++){    printf("%d ",num[i]);}printf("\n");    //return ;}for(int i=1;i<=n;i++){if(use[i]==0){    use[i] = 1;        num[t]=i;                dfs(n,t+1);        use[i] = 0;}}}int main(){    int n;while(scanf("%d",&n)!=EOF){ dfs(n,0);}return 0;}