text: #include <stdio.h>
  char *pr(char *str);
  
  int main()
  {
      char *x;
      x = pr("Ho Ho Ho!");
      return 0;
  }
  
  char *pr(char *str)
  {
      char *pc;
      pc = str;
      while (*pc)
          putchar(*pc++);
      do
      {
          putchar(*--pc);
      } while (pc - str);
      return (pc);
  }
  