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

struct node
{
  int data;
  struct node * left, * right;
};

struct node * const_node(int x)
{ void * v;
  struct node * p;
  v = malloc(sizeof(struct node));
  p = (struct node *) v;
  p->data = x;
  p->left = NULL;
  p->right = NULL;
  return p; }

void print_tree(int fd, struct node * p)
{ if (p == NULL)
    return;
  print_tree(fd, p->left);
  printf("%d\n", p->data);
  write(fd, & p->data, sizeof(p->data));
  print_tree(fd, p->right); }

struct node * insert_node(struct node * p, int x)
{ if (p == NULL)
    p = const_node(x);
  else if (x < p->data)
    p->left = insert_node(p->left, x);
  else
    p->right = insert_node(p->right, x);
  return p; }

void fill_with_randoms(int * nums, int number)
{ int i;
  for (i = 0; i < number; i += 1)
    nums[i] = random() % 1000; }

void print(int * nums, int number)
{ int i;
  for (i = 0; i < number; i += 1)
    printf("%3d ", nums[i]);
  printf("\n"); }

void shuffle(int * nums, int number)
{ int i;
  for (i = 0; i < 4 * number; i += 1)
  { int p = random() % number;
    int z = nums[0];
    nums[0] = nums[p];
    nums[p] = z; } }

int main(int argc, char * argv[])
{ struct node * t = NULL;
  int x, number, i, f;
  int * nums;
  if (argc != 2)
  { fprintf(stderr, "usage: %s number-of-numbers\n", argv[0]);
    exit(1); } 
  number = atol(argv[1]);

  srandomdev();
  f = open("storage", O_WRONLY | O_CREAT | O_TRUNC, 0644);
  if (f < 0)
  { perror("cant open storage");
    exit(1); }
  nums = (int *)malloc(number * sizeof(int));
  fill_with_randoms(nums, number);
  for (i=0; i<number; i+=1)
    t = insert_node(t, nums[i]);
  print_tree(f, t); }