LeetCode - Valid Parenthesis String

Question Definition

Given a string containing only three types of characters: ‘(‘, ‘)’ and ‘*’, write a function to check whether this string is valid. We define the validity of a string by these rules:

1. Any left parenthesis ‘(‘ must have a corresponding right parenthesis ‘)’.
2. Any right parenthesis ‘)’ must have a corresponding left parenthesis ‘(‘.
3. Left parenthesis ‘(‘ must go before the corresponding right parenthesis ‘)’.
4. ‘*’ could be treated as a single right parenthesis ‘)’ or a single left parenthesis ‘(‘ or an empty string.
5. An empty string is also valid. Example 1:

   Input: "()"
   Output: True
   

   Example 2:

   Input: "(*)"
   Output: True
   

   Example 3:

   Input: "(*))"
   Output: True
   

   Note:

6. The string size will be in the range [1, 100].

   Java Solution