Java O(n) solution to see if all parentheses in a string have a corrisponding pair in the correct order. Beats 99% of submissions. 1ms
Instructions: 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:
Input: s = "()" Output: true Example 2:
Input: s = "()[]{}" Output: true Example 3:
Input: s = "(]" Output: false Example 4:
Input: s = "([)]" Output: false Example 5:
Input: s = "{[]}" Output: true
Constraints:
1 <= s.length <= 104 s consists of parentheses only '()[]{}'.
Link to Question: https://leetcode.com/problems/valid-parentheses/