66 lines
1.4 KiB
Python
66 lines
1.4 KiB
Python
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from random import choice
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class Node(object):
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def __init__(self, value=None, left=None, right=None):
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self.value = value
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self.left = left
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self.right = left
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def p(node, indent=0):
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print(indent * ' ' + '|-' + str(node.value))
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if node.left is not None:
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p(node.left, indent=indent + 2)
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if node.right is not None:
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p(node.right, indent=indent + 2)
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# read trees (i.e. traversing, parsing)
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# write trees (i.e. generating, printing)
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def random(d=0):
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left = None
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right = None
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if choice([True, False]):
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left = random(d + 1)
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if choice([True, False]):
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right = random(d + 1)
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return Node(
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value=d,
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left=left,
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right=right,
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)
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################################################################################
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# DFTs can be:
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# - imperative (mutable)
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# - functional (immutable)
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# - iterative
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# - recursive
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################################################################################
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# Iterative
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def traverse(node, f):
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stack = [(node, 0)]
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while len(stack):
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node, depth = stack.pop()
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f(node, depth)
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print(depth)
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if node.left is not None:
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stack.append((node.left, depth + 1))
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if node.right is not None:
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stack.append((node.right, depth + 1))
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print('----------------------------------------------------------------------')
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for _ in range(10):
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traverse(random(), lambda _, d: print(d))
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print()
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