南阳理工19题

#include <cstdio>#include <string>#include <algorithm>using namespace std;int n,m,used[10];char ans[11];void dfs(int x,int num){if(num==m-1){ans[m]='\0';printf("%s\n",ans);return;}int i;for(i=1;i<=n;i++){if(!used[i]){used[i]=1;ans[num+1]=i+'0';dfs(i,num+1);used[i]=0;}}}int main(){int i,t;scanf("%d",&t);while(t--){scanf("%d%d",&n,&m);for(i=1;i<=n;i++){memset(used,0,sizeof(used));used[i]=1;ans[0]=i+'0';dfs(i,0);}}return 0;}