#include <stdio.h>
#include <string.h>
#define MAX_N 30

main()
{
  int n;
  printf("n=?\n");
  scanf("%d", &n);
  S(n, "A ");
}

S(int n, char *s)
{
  char news1[MAX_N],news2[MAX_N];
  if (n==1)
    {
      printf("%s%s\n", s,"* B");
      printf("%s%s\n", s,"_ B");
      return;
    }
  if (n==2)
    {
      printf("%s%s\n", s,"* _ B");
      printf("%s%s\n", s,"_ * B");
      printf("%s%s\n", s,"_ _ B");
      return;
    }
  S(n-2, strcat(strcpy(news1,s),"* _ "));
  S(n-1, strcat(strcpy(news2,s),"_ "));
}