Balanced Parentheses

StackString

Given a string consisting of parentheses characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid. A string is considered valid if all the brackets are opened and closed appropriately and nested correctly. For every opening bracket, there should be a corresponding matching closing bracket of the same type.

Example 1

Input

[
  "()"
]

Output

true

Explanation. Single type of balanced parentheses.

Example 2

Input

[
  "()[]{}"
]

Output

true

Explanation. Multiple types of balanced parentheses mixed but appropriately closed.

Example 3

Input

[
  "(]"
]

Output

false

Explanation. Parentheses are not matching.

Example 4

Input

[
  "([)]"
]

Output

false

Explanation. Brackets are closed in the wrong order.

Example 5

Input

[
  "{[]}"
]

Output

true

Explanation. Multiple brackets properly nested.

Follow-up: How would you handle different types of brackets, such as angle brackets '<' and '>'?

Constraints:

The input string will only contain the characters: '(', ')', '{', '}', '[' and ']'.

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