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85 lines
2.2 KiB
Python
85 lines
2.2 KiB
Python
3 years ago
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from random import randint
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# Description of a node
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class TreeNode (object):
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def __init__ (self, value = None):
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self.value = value
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self.left = None
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self.right = None
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"""
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This function defines a root for the tree and initiates
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the process of looping through the values and inserting
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them into the tree.
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"""
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def make_tree (values):
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tree = None
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for value in values:
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tree = insert(tree, value)
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return tree
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"""
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Adds a node to the tree
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"""
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def insert (root, value, key = lambda value: value):
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# Test whether there is a node at the current location
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if not root:
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# If not, insert the node here
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root = TreeNode()
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root.value = value
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else:
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# There is a node, compare value to be inserted
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# and the value of the node to decide whether the
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# node should be attached to the left or the right
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if key(value) < key(root.value):
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root.left = insert(root.left, value, key)
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else:
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root.right = insert(root.right, value, key)
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return root
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"""
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Measures the depth of a (sub)tree
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"""
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def measure_tree (node):
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if node:
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# If there is a node, measure the depth
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# of the left and right node
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depth_left = measure_tree(node.left)
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depth_right = measure_tree(node.right)
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# Return the answer with the highest value
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# and add one
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return max(depth_left, depth_right) + 1
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else:
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# There isn't a node, answer with the value 0
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return 0
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def traverse_tree (node):
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# Test whether there is a node
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if node:
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# If there is a node, ask its left node to traverse
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tree_left = traverse_tree(node.left)
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# and ask the same for its right node
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tree_right = traverse_tree(node.right)
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# Then combine into a new list:
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# the list answered by the left node
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# with the value of the node itself
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# And the list answered by the right node
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#
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# Give this new list as an answer to the root node
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return tree_left + [ node.value ] + tree_right
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else:
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# There is no node, return an empty list
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return []
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if __name__ == '__main__':
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values = [randint(0, 100) for _ in range(15)]
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tree = make_tree(values)
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print(values, tree.value, tree.left.value if tree.left else None, tree.right.value if tree.right else None, measure_tree(tree), traverse_tree(tree))
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