71 lines
1.9 KiB
Python
71 lines
1.9 KiB
Python
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from collections import deque
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class Node(object):
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# __init__ :: T(A)
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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 = right
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# insert_left :: T(A) -> A -> T(A)
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def insert_left(self, value):
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self.left = Node(value)
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return self.left
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# insert_right :: T(A) -> A -> T(A)
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def insert_right(self, value):
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self.right = Node(value)
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return self.right
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# is_superbalanced :: T(A) -> Bool
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def is_superbalanced(self):
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xs = deque()
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min_depth, max_depth = float('inf'), float('-inf')
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xs.append((self, 0))
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while xs:
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x, d = xs.popleft()
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# Only redefine the depths at leaf nodes
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if not x.left and not x.right:
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min_depth, max_depth = min(min_depth, d), max(max_depth, d)
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if x.left:
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xs.append((x.left, d + 1))
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if x.right:
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xs.append((x.right, d + 1))
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return max_depth - min_depth <= 1
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# __repr__ :: T(A) -> String
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def __repr__(self):
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result = ''
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xs = deque()
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xs.append((self, 0))
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while xs:
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node, indent = xs.popleft()
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result += '{i}{x}\n'.format(i=' ' * indent, x=node.value)
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if node.left:
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xs.append((node.left, indent + 2))
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if node.right:
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xs.append((node.right, indent + 2))
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return result
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# from_array :: List(A) -> T(A)
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def from_array(values):
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xs = deque()
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root = Node()
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xs.append(root)
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for value in values:
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node = xs.popleft()
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node.value = value
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node.left = Node()
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xs.append(node.left)
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node.right = Node()
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xs.append(node.right)
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return root
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x = from_array([1, 1, 1, 1, 1, 1, 1])
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print(x)
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print(x.is_superbalanced())
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x = Node(1, Node(2), Node(3))
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print(x)
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print(x.is_superbalanced())
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