Description

Given a string s containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.

An input string is valid if:

• Open brackets must be closed by the same type of brackets.
• Open brackets must be closed in the correct order.

Example 1:

Example 2:

Example 3:

Example 4:

Note:

Runner expects a single line stdin with a string (e.g. ()[]{}) and prints true or false.