def draw_binary_tree_dx():
dummy = random.uniform(0, 1)
if bern([dummy]) == 0:
BinaryTree.generated_black_root_node = True
return draw_black_rooted_btree_dx()
else:
BinaryTree.generated_black_root_node = False
return draw_white_rooted_btree_dx()
def draw_binary_tree():
#This probabiliy has to be calculated ---> just a dummy here
dummy = random.uniform(0, 1)
if bern([dummy]) == 0:
BinaryTree.generated_black_root_node = True
return draw_black_rooted_btree()
else:
BinaryTree.generated_black_root_node = false
return draw_white_rooted_btree()
def draw_empty_or_rooted_btree(color):
dummy = random.uniform(0, 1)
decision_1 = bern([dummy])
if decision_1 == 0:
#Empty left child
return None
else:
if color == 0:
#Generate new black-rooted binary tree
return draw_black_rooted_btree()
else:
#Generate new white-rooted binary tree
return draw_white_rooted_btree()
def draw_white_rooted_btree_dx():
dummy_1 = random.uniform(0, 1)
decision = bern([dummy_1])
self.numb_white_nodes += 1
self.numb_nodes += 1
left_child = None
right_child = None
if decision == 0:
left_child = draw_empty_or_rooted_btree(0)
right_child = draw_black_rooted_btree_dx()
else:
left_child = draw_black_rooted_btree_dx()
right_child = draw_empty_or_rooted_btree(0)
return BinaryTree(left_child, right_child)
def draw_black_rooted_btree_dx():
dummy_1 = random.uniform(0, 1)
dummy_2 = (1 - dummy_1) * 1 / 3
dummy_3 = (1 - dummy_1) * 2 / 3
decision = bern([dummy_1, dummy_2, dummy_3])
if decision == 0:
return draw_black_rooted_btree()
else:
self.numb_black_nodes += 1
self.numb_nodes += 1
left_child = None
right_child = None
if decision == 1:
left_child = draw_empty_or_rooted_btree(1)
right_child = draw_white_rooted_btree_dx()
else:
left_child = draw_white_rooted_btree_dx()
right_child = draw_empty_or_rooted_btree(1)
return BinaryTree(left_child, right_child)