#include <stdio.h>

 int a[];

 int vis[];

 int n;

 void dfs(int step)//step是当前已经进去排列的个数

 {

     if (step == n)//如果找到n个之后，打印一次

     {

         for (int i = ; i < n; i++)

             printf("%d ", a[i]);

         puts("");

         return ;

     }

     for (int i = ; i <= n; i++)

     {

         if (vis[i] == )//排列中没有此数字，就将它加入到排列中

         {

             vis[i] = ;

             a[step] = i;

             dfs(step + );

             vis[i] = ;

         }

     }

 }

 int main()

 {

     while (scanf("%d", &n) == )

     {

         dfs();

     }

     return ;

 }

 #include <stdio.h>

 #include <string.h>

 int n, r;

 int a[];

 int vis[];

 void dfs(int step)

 {

     if (step == r + )

     {

         for (int i = ; i <= r; i++)

             printf("%d", a[i]);

         puts("");

         return ;

     }

     for (int i = n; i > ; i--)

     {

         if (vis[i] ==  && i < a[step - ])//满足逆序

         {

             vis[i] = ;

             a[step] = i;

             dfs(step + );

             vis[i] = ;

         }

     }

 }

 int main()

 {

     a[] = ;

     while (scanf("%d %d", &n, &r) == )

     {

         memset(vis, , sizeof(vis));

         dfs();

     } 

     return ;

 }