20 lines
700 B
Python
20 lines
700 B
Python
# recursive solution: takes O(n) time
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# first get the height of the tree, then recusivly update the value
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def printTree(self, root):
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def get_height(root):
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if not root: return 0
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return 1 + max(get_height(root.left), get_height(root.right))
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def update(res, node, row, left, right):
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if not node: return
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mid = (left + right) // 2
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res[row][mid] = str(node.val)
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update(res, node.left, row + 1, left, mid - 1)
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update(res, node.right, row + 1, mid + 1, right)
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height = get_height(root)
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width = 2 ** height - 1
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res = [['' for _ in range(width)] for _ in range(height)]
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update(res, root, 0, 0, width - 1)
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return res |