Python/data_structures/AVL/AVL.py

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'''
A AVL tree
'''
class Node:
def __init__(self, label):
self.label = label
self.left = None
self.rigt = None
self.parent = None
self.height = 0
def getLabel(self):
return self.label
def setLabel(self, label):
self.label = label
def getLeft(self):
return self.left
def setLeft(self, left):
self.left = left
def getRight(self):
return self.rigt
def setRight(self, right):
self.rigt = right
def getParent(self):
return self.parent
def setParent(self, parent):
self.parent = parent
def setHeight(self, height):
self.height = height
def getHeight(self, height):
return self.height
class AVL:
def __init__(self):
self.root = None
self.size = 0
def insert(self, value):
node = Node(value)
if self.root is None:
self.root = node
self.size = 1
else:
# Same as Binary Tree
dad_node = None
curr_node = self.root
while True:
if curr_node is not None:
dad_node = curr_node
if node.getLabel() < curr_node.getLabel():
curr_node = curr_node.getLeft()
else:
curr_node = curr_node.getRight()
else:
if node.getLabel() < dad_node.getLabel():
dad_node.setLeft(node)
dad_node.setHeight(dad_node.getHeight() + 1)
if (dad_node.getRight().getHeight() -
dad_node.getLeft.getHeight() > 1):
self.rebalance(dad_node)
else:
dad_node.setRight(node)
dad_node.setHeight(dad_node.getHeight() + 1)
if (dad_node.getRight().getHeight() -
dad_node.getLeft.getHeight() > 1):
self.rebalance(dad_node)
break
def rebalance(self, node):
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if (node.getRight().getHeight() -
node.getLeft.getHeight() > 1):
if (node.getRight().getHeight() >
node.getLeft.getHeight()):
pass
else:
pass
pass
elif (node.getRight().getHeight() -
node.getLeft.getHeight() > 2):
if (node.getRight().getHeight() >
node.getLeft.getHeight()):
pass
else:
pass
pass
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pass
def rotate_left(self, node):
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# TODO: is this pythonic enought?
aux = node.getLabel()
node = aux.getRight()
node.setHeight(node.getHeight() - 1)
node.setLeft(Node(aux))
node.getLeft().setHeight(node.getHeight() + 1)
node.getRight().setHeight(node.getRight().getHeight() - 1)
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def rotate_right(self, node):
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aux = node.getLabel()
node = aux.getLeft()
node.setHeight(node.getHeight() - 1)
node.setRight(Node(aux))
node.getLeft().setHeight(node.getHeight() + 1)
node.getLeft().setHeight(node.getLeft().getHeight() - 1)
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def double_rotate_left(self, node):
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self.rotate_right(node.getRight().getRight())
self.rotate_left(node)
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def double_rotate_right(self, node):
self.rotate_left(node.getLeft().getLeft())
self.rotate_right(node)