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Validate Well-Formed JSON
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Validate Well-Formed JSON

HardPython

Problem

Tell me about how you would write a function to parse a string and verify it is well-formed JSON by matching opening and closing enclosures like () {} [].

Implement is_well_formed_json(s) without using a JSON parsing library. The function must return True only for a complete valid JSON value, including nested arrays and objects, strings with escapes, numbers, true, false, and null; otherwise return False.

Input: a string s. Output: a Boolean.

Constraints

  • 0 <= len(s) <= 10^5
  • The input contains ordinary Python string characters
  • Nesting depth is at most 500 for valid inputs
  • Do not call a JSON parsing library

Function Signature

def is_well_formed_json(s):
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