Balanced Parentheses Checker

StackString

Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid. An input string is valid if:\n1. Open brackets must be closed by the same type of brackets.\n2. Open brackets must be closed in the correct order.\n3. Each close bracket has a corresponding open bracket of the same type.

Example 1

Input

[
  "()"
]

Output

True

Explanation. The parenthesis pair is matched correctly.

Example 2

Input

[
  "()[]{}"
]

Output

True

Explanation. All types of brackets are matched correctly and in the correct order.

Example 3

Input

[
  "(]"
]

Output

False

Explanation. The parentheses are not matched correctly; a closing square bracket cannot close an opening parenthesis.

Example 4

Input

[
  "([)]"
]

Output

False

Explanation. The brackets are not closed in the correct order.

Example 5

Input

[
  "{[]}"
]

Output

True

Explanation. All brackets are matched correctly and nested properly.

Follow-up: Consider cases with other characters or empty strings to check how your function handles unexpected input.

Constraints:

1. The string can include characters: '(', ')', '{', '}', '[' and ']' only.\n2. The length of the string will be between 1 and 10,000.

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