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Balanced Brackets Validator
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Balanced Brackets Validator

EasyPython

Problem

Noblis software may receive compact configuration or message fragments containing parentheses and square brackets. Implement a method that determines whether every opening delimiter is closed by the correct delimiter in the correct order.

A string is valid when each ( has a matching ), each [ has a matching ], and delimiters are properly nested. Ignore all characters other than (, ), [, and ].

Formal Specification

Implement is_balanced(s), where s is a string. Return True if the relevant delimiters are balanced and properly nested; otherwise, return False. The empty string is considered valid.

Constraints

  • 0 <= len(s) <= 10^5
  • s contains printable characters
  • Only parentheses and square brackets affect validity
  • Return a boolean result

Function Signature

def is_balanced(s):
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