forked from hofmannol/AlgoDatSoSe25
63 lines
2.0 KiB
Python
63 lines
2.0 KiB
Python
from vorlesung.L05_binaere_baeume.bin_tree_node import BinaryTreeNode
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class AVLTreeNode(BinaryTreeNode):
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def __init__(self, value):
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super().__init__(value)
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self.parent = None
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self.balance = 0
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def __repr__(self):
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return f"TreeNode(id={id(self)} value={self.value}, left={self.left}, right={self.right})"
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def gv_rep(self, row, col):
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"""Returns the graphviz representation of the node."""
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return f"{id(self)} [label=\"{self.value}\", pos=\"{col},{-row}!\", xlabel=\"{self.balance}\"];\n"
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def update_balance(self):
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left_height = self.left.height() if self.left else 0
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right_height = self.right.height() if self.right else 0
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self.balance = right_height - left_height
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def right_rotate(self):
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new_root = self.left
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new_root.parent = self.parent
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self.left = new_root.right
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if self.left:
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self.left.parent = self
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new_root.right = self
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self.parent = new_root
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if new_root.parent:
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if new_root.parent.left is self:
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new_root.parent.left = new_root
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else:
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new_root.parent.right = new_root
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self.update_balance()
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new_root.update_balance()
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return new_root
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def left_rotate(self):
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new_root = self.right
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new_root.parent = self.parent
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self.right = new_root.left
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if self.right:
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self.right.parent = self
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new_root.left = self
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self.parent = new_root
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if new_root.parent:
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if new_root.parent.left is self:
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new_root.parent.left = new_root
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else:
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new_root.parent.right = new_root
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self.update_balance()
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new_root.update_balance()
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return new_root
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def right_left_rotate(self):
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self.right = self.right.right_rotate()
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return self.left_rotate()
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def left_right_rotate(self):
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self.left = self.left.left_rotate()
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return self.right_rotate()
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