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Python BasicsEasy
Balanced Parenthesis Problem
Learn how to solve the 'Balanced Parenthesis Problem' problem. This detailed resource details brute force and optimized approaches.
Problem Statement
Easy
Write a function is_balanced(s) that takes a string s containing only the characters '(', ')', '{', '}', '[' and ']', and returns True if the parentheses are balanced and properly nested, False otherwise. An empty string is considered balanced.
Constraints
- •0 <= len(s) <= 10^4
- •s consists only of '(', ')', '{', '}', '[', ']'
Examples
Example 1
Input
s = '({[]})'Output
True
Explanation
Each opening bracket has a matching closing bracket in the correct order: ( matches ), { matches }, [ matches ].
Example 2
Input
s = '({[})'Output
False
Explanation
The [ is closed by } which is a mismatch.
Example 3
Input
s = ''
Output
True
Explanation
An empty string is considered balanced.
Need a Hint?
Use simple arithmetic operators (like modulo `%`, division `//`), conditional checks, or loops to inspect number properties.
Edge Cases to Watch
- Empty list or null input variables
- Single item lists/arrays
- Extremely large input bounds causing integer or stack overflow
Ready to Solve?
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