Please solve the programming task below using a self-contained code snippet in a markdown code block.

Given a balanced parentheses string s, return the score of the string.
The score of a balanced parentheses string is based on the following rule:

"()" has score 1.
AB has score A + B, where A and B are balanced parentheses strings.
(A) has score 2 * A, where A is a balanced parentheses string.

 
Please complete the following python code precisely:
```python
class Solution:
    def scoreOfParentheses(self, s: str) -> int:
```