Valid Parentheses

StackString

Problem Statement

Given a string s containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid. A string is valid if open brackets are closed by the same type of brackets in the correct order.

Examplespublic test cases

Simple valid: () → True
Input is_valid("()")
Output True
Mixed valid: ()[]{} → True
Input is_valid("()[]{}")
Output True
Invalid nesting: (] → False
Input is_valid("(]")
Output False
Nested valid: {[()]} → True
Input is_valid("{[()]}")
Output True

Complexity

TimeO(n)

SpaceO(n)

Asked By

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