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Construct Tree From String
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Construct Tree From String

MediumPython

Problem

Construct a tree from a string format.

Use the format value(left,right), where # represents an empty child. Return the tree as a nested list [value, left, right], or None for an empty tree. Implement build_tree(data) and preserve negative and multi-digit values. The input contains no whitespace and is guaranteed to follow the format.

Constraints

  • 0 <= data.length <= 300
  • Values are signed decimal integers in the range -10^9 to 10^9
  • The input contains no whitespace
  • The string is guaranteed to follow the specified format
  • The tree contains at most 150 nodes

Function Signature

def build_tree(data):
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