Practice Valid Parentheses

Read the task, work through the examples, and check your approach against the constraints. Use the original LeetCode task for coding and submissions.

Easy#20

LeetCode Problem

Valid Parentheses

String Stack

Problem Statement

A string contains only (), [], and {} brackets. Decide whether all brackets form a valid nesting: each closing bracket must match the type of the most recent unmatched opening bracket, and no bracket may remain unmatched. Adjacent complete groups are allowed. Practice approach: Push opening brackets on a stack. For a closer, reject an empty stack or a mismatched top; otherwise pop. Accept only if the stack is empty after the scan. Time and worst-case space are O(n).

Source: Valid Parentheses on LeetCode. Use the original task for its coding environment and submissions.

Examples

# Example 1

Input

s = "()"

Output

true

# Example 2

Input

s = "()[]{}"

Output

true

# Example 3

Input

s = "(]"

Output

false

# Example 4

Input

s = "([])"

Output

true

# Example 5

Input

s = "([)]"

Output

false

Constraints

1 <= s.length <= 10000

s contains only (, ), [, ], {, and }.

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Practice Valid Parentheses

Valid Parentheses

Problem Statement

Examples

# Example 1

# Example 2

# Example 3

# Example 4

# Example 5

Constraints

Related LeetCode Problems

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