Check whether brackets are balanced
Company: Walmart Labs
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: medium
Interview Round: Technical Screen
## Problem
Given a string `s` that may contain bracket characters, determine whether the brackets are **properly balanced**.
Treat the following as brackets:
- Parentheses: `(` and `)`
- Square brackets: `[` and `]`
- Curly braces: `{` and `}`
All other characters (letters, digits, spaces, punctuation) should be ignored.
A string is balanced if:
1. Every opening bracket is closed by the **same type** of bracket.
2. Brackets are closed in the **correct order** (proper nesting).
## Input/Output
- **Input:** string `s`
- **Output:** boolean `true` if balanced, otherwise `false`
## Examples
- `"(a[b]{c})"` → `true`
- `"([)]"` → `false`
- `"(("` → `false`
- `""` → `true`
## Constraints (assume)
- `0 ≤ len(s) ≤ 2 * 10^5`
Quick Answer: This question evaluates a candidate's competency in string processing and bracket-matching concepts, testing familiarity with linear-time algorithms and simple data structures for recognizing correct nesting and matching of parentheses, brackets, and braces.