最长有效括号：Python 动态规划解法

最长有效括号

以下是使用动态规划解决该问题的 Python 实现。

class Solution:
    def longestValidParentheses(self, s: str) -> int:
        n = len(s)
        if n == 0:
            return 0
        dp = [0] * n
        res = 0
        for i in range(n):
            if i > 0 and s[i] == ")":
                if s[i - 1] == "(":
                    dp[i] = dp[i - 2] + 2 if i >= 2 else 2
                elif s[i - 1] == ")" and i - dp[i - 1] - 1 >= 0 and s[i - dp[i - 1] - 1] == "(":
                    dp[i] = dp[i - 1] + 2 + (dp[i - dp[i - 1] - 2] if i - dp[i - 1] - 2 >= 0 else )
             dp[i] > res:
                res = dp[i]
         res