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E

Valid Parentheses

#58
stackstring

Use stack to match closing brackets with their corresponding opening brackets.

Example:

Input:s='([)]'
Output:false (wrong order)

Common Mistakes:

  • Not checking if stack is empty before popping
  • Forgetting to check stack is empty at end
  • Using if-else chains instead of map for cleaner code
  • Not handling interleaved brackets like '([)]'

Notes:

Classic stack problem. Time O(n), Space O(n). Foundation for more complex parsing problems.

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Valid Parentheses