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Valid Parentheses

Given a string s containing just the characters '(', ')', '{', '}', '[', and ']', determine if the input string is valid.

An input string is valid if:

Input:

()[]{}

Output:

True

Reasoning:

The input string ()[]{} is processed from left to right, with each opening bracket being pushed onto a stack.
When a closing bracket is encountered, the top of the stack is checked to ensure it contains the corresponding opening bracket: ( matches ), { matches }, and [ matches ].
The string is valid if the stack is empty at the end, meaning all brackets were properly closed: () is closed, [] is closed, and {} is closed.
Since all brackets in the input string are properly closed in the correct order, the output is True.

Editor

Python 3.13.1

0/0

Run code to see test results.