82 lines
2.2 KiB
Python
82 lines
2.2 KiB
Python
from vorlesung.L05_binaere_baeume.avl_tree_node import AVLTreeNode
|
|
from vorlesung.L05_binaere_baeume.bin_tree import BinaryTree
|
|
from utils.algo_context import AlgoContext
|
|
from utils.algo_array import Array
|
|
|
|
|
|
class AVLTree(BinaryTree):
|
|
|
|
def __init__(self, ctx: AlgoContext):
|
|
super().__init__(ctx)
|
|
|
|
def new_node(self, value):
|
|
return AVLTreeNode(value, self.ctx)
|
|
|
|
def balance(self, node: AVLTreeNode):
|
|
node.update_balance()
|
|
if node.balance == -2:
|
|
if node.left.balance <= 0:
|
|
node = node.right_rotate()
|
|
else:
|
|
node = node.left_right_rotate()
|
|
elif node.balance == 2:
|
|
if node.right.balance >= 0:
|
|
node = node.left_rotate()
|
|
else:
|
|
node = node.right_left_rotate()
|
|
if node.parent:
|
|
self.balance(node.parent)
|
|
else:
|
|
self.root = node
|
|
|
|
def insert(self, value):
|
|
insert_generator = self.insert_stepwise(value)
|
|
node, parent = None, None
|
|
while True:
|
|
try:
|
|
node, parent = next(insert_generator)
|
|
except StopIteration:
|
|
break
|
|
return node, parent
|
|
|
|
def insert_stepwise(self, value):
|
|
node, parent = super().insert(value)
|
|
yield None, None
|
|
node.parent = parent
|
|
if parent:
|
|
self.balance(parent)
|
|
return node, parent
|
|
|
|
def delete(self, value):
|
|
node, parent = super().delete(value)
|
|
if node:
|
|
node.parent = parent
|
|
if parent:
|
|
self.balance(parent)
|
|
|
|
def graph_filename(self):
|
|
return "AVLTree"
|
|
|
|
|
|
if __name__ == "__main__":
|
|
ctx = AlgoContext()
|
|
tree = AVLTree(ctx)
|
|
|
|
values = Array.from_file("data/seq2.txt", ctx)
|
|
for cell in values:
|
|
tree.insert(cell.value)
|
|
|
|
def print_node(node, indent=0, level=0):
|
|
print((indent * 3) * " ", node.value)
|
|
|
|
print("In-order traversal:")
|
|
tree.in_order_traversal(print_node)
|
|
print("\nTree structure traversal:")
|
|
tree.tree_structure_traversal(print_node)
|
|
|
|
tree.insert(9)
|
|
print("\nDeleting 5:")
|
|
tree.delete(5)
|
|
print("In-order traversal after deletion:")
|
|
tree.in_order_traversal(print_node)
|