#include <stdio.h>
#include <stdlib.h>

#define null -1
typedef int PNODE1;   /* a node */
char value[100];      /* value */
int lch[100];         /* left child links */
int rch[100];         /* right child links */
int mem = null;       /* fake top of memory */

/* function Insert1 ------------------------------------------- */
PNODE1 Insert1(PNODE1 n,char c)
{
  if (n == null) {
    n = ++mem;
    value[n] = c;
    lch[n] = rch[n] = null;
    return n;
  }
  if (c < value[n])
    lch[n] = Insert1(lch[n],c);
  else
    rch[n] = Insert1(rch[n],c);
  return n;
}/*end Insert1*/


/* function Show1 --------------------------------------------- */
void Show1(PNODE1 n)
{
  if (n == null) return;
  Show1(lch[n]);
  printf(" %c",value[n]);
  Show1(rch[n]);
}/*end Show1*/