Valid Parentheses

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

LeetCode: Valid Parentheses

An input string is valid if:

1. Open brackets must be closed by the same type of brackets
2. Open brackets must be closed in the correct order
3. Every close bracket has a corresponding open bracket of the same type

Example:

Input: s = "()"
Output: true

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

Input: s = "(]"
Output: false

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

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