LeetCode Valid Parentheses Problem: Stack Method Beats Recursion by 80x

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A developer tackled LeetCode's Valid Parentheses problem, which requires checking whether bracket sequences in a string are correctly matched and ordered. Three approaches were implemented in Python: a replace-based loop, a stack method, and a recursive solution. The stack approach proved most efficient, running in just 7ms with 12.4MB memory, while recursion consumed 416MB and took 579ms. The replace method fell in between at 225ms. The exercise highlighted that while recursion may seem intuitive, the problem is fundamentally best suited to a stack-based solution.

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