Balanced Brackets

Difficulty: Easy · Topics: Stack, String · Acceptance: 100.0% of 1 submissions

Difficulty: Easy | Tags: Stack, String

Description

Given a string containing only the characters (, ), {, }, [, and ], determine if the brackets are properly matched and nested.

Implement:

isBalanced(String s) → boolean

Return true if every opening bracket has a corresponding closing bracket of the same type and brackets are properly nested. An empty string is considered balanced.

Examples

Example 1:

Input:  "()"
Output: true

Example 2:

Input:  "({[]})"
Output: true

Example 3:

Input:  "{[}]"
Output: false
Explanation: Brackets are not properly nested.

Example 4:

Input:  ""
Output: true
Explanation: Empty string is considered balanced.

Constraints

0 ≤ s.length ≤ 10⁴
s consists only of (){}[] characters.

Hints

Hint 1

Use a stack: push opening brackets, pop on closing brackets and verify they match.

Hint 2

If the stack is non-empty at the end, there are unmatched opening brackets.

Practice this problem

Solve Balanced Brackets in the browser