Challenge Statement
- 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.
- This challenge corresponds to LeetCode #20.
Constraints
1 <= s.length <= 104sconsists of parentheses only ‘()[]{}’.
Example 1:
Input: s = "()"
Output: True
Example 2:
Input: s = "()[]{}"
Output: True
Example 3:
Input: s = "(]"
Output: False
Solution
Below is my solution and some test cases. The solution has a linear time complexity of O(n) and a linear space complexity O(n), where n is the length of the string s.