from TreeNode import *

class HeapTree:

  def __init__(self):
    self._queue = None
    self._size = 0

  def __str__(self):
    if self._queue == None:
      return ' '
    else:
      return HeapTree.tree2string(self._queue)

  @classmethod
  def tree2string(cls,node):
    if node != None:
      return str(node._data)+' '+HeapTree.tree2string(node._left)+HeapTree.tree2string(node._right)
    else:
      return ''

  def is_empty(self):
    return self._queue == None

  @classmethod
  def binary(cls,num):
    result = []
    while num > 0:
      result = [num%2] + result
      num //= 2
    return result

  def insert(self,data):

  def delete_min(self):