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Valid Parentheses Procedure
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Valid Parentheses Procedure

EasyPython

Problem

ServiceNow expression and configuration syntax can contain nested parentheses, square brackets, and braces. Given a string containing only the bracket characters (), [], and {}, determine whether the brackets are correctly matched and properly nested.

A string is valid when every opening bracket has the corresponding closing bracket, closing brackets appear in last-in, first-out order, and no closing bracket appears without a matching opener.

Formal Specification

Implement is_valid_brackets(s), where s is a string. Return True if all brackets are valid and False otherwise. The input contains only (, ), [, ], {, and }.

Constraints

  • 0 <= len(s) <= 10^5
  • s contains only the characters (, ), [, ], {, and }
  • Return True only when every bracket is correctly matched and nested

Function Signature

def is_valid_brackets(s):
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