856. Score of Parentheses

https://leetcode.com/problems/score-of-parentheses/

Given a balanced parentheses string S, compute the score of the string 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.

 

Example 1:

Input: "()"
Output: 1

Example 2:

Input: "(())"
Output: 2

Example 3:

Input: "()()"
Output: 2

Example 4:

Input: "(()(()))"
Output: 6

 

Note:

1. S is a balanced parentheses string, containing only ( and ).
2. 2 <= S.length <= 50

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Intuition

Only () contribute to final score

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