Valid Parentheses

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.
• Every close bracket has a corresponding open bracket of the same type.

Example 1:

      Input: s = "()"
      Output: true
      

Example 2:

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

Example 3:

      Input: s = "(]"
      Output: false
      

Example 4:

      Input: s = "([])"
      Output: true
      

Constraints:

• 1 <= s.length <= 10⁴
• s consists of parentheses only: '()[]{}'.