import "io"
import "heap"

manifest
{ node_data = 0,
  node_left = 1, 
  node_right = 2,
  node_size = 3 }

let new_node(d) be
{ let r = newvec(node_size);
  r ! node_data := d;
  r ! node_left := nil;
  r ! node_right := nil;
  resultis r }

let print(t) be
{ if t = nil then
    return;
  print(t ! node_left);
  out("%d ", t ! node_data);
  print(t ! node_right) }

let insert(v, t) be
{ test t = nil then
    t := new_node(v)
  else test v < t ! node_data then
    t ! node_left := insert(v, t ! node_left)
  else
    t ! node_right := insert(v, t ! node_right);
  resultis t }

let start() be
{ let root = nil, v;
  init();
  for i = 0 to 19 do
  { v := random(100);
    out("%d ", v);
    root := insert(v, root) }
  out("\n");
  print(root);
  out("\n") }