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🔥Valid Parentheses: Syntax Tree ValidatorEasy
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Valid Parentheses: Syntax Tree Validator

Targeted in FAANG & Tech OA:AmazonMicrosoftGoogleBloomberg
Real-World Engineering Context
Directly used in compilers and AST parsers (such as Babel, SWC, and TypeScript compiler) to validate code syntax before compilation.
Given a string `s` containing just the characters `'('`, `')'`, `'{'`, `'}'`, `'['` and `']'`, determine if the input string is valid. An input string is valid if: 1. Open brackets must be closed by the same type of brackets. 2. Open brackets must be closed in the correct order. 3. Every close bracket has a corresponding open bracket of the same type.

Sample Test Cases

Input: ["()"]
Expected: true
Input: ["()[]{}"]
Expected: true
Input: ["(]"]
Expected: false
Input: ["{[]}"]
Expected: true

Constraints

  • 1 <= s.length <= 10^4
  • s consists of parentheses only '()[]{}'.
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