32. Longest Valid Parentheses *HARD*

Given a string containing just the characters '(' and ')', find the length of the longest valid (well-formed) parentheses substring.

For "(()", the longest valid parentheses substring is "()", which has length = 2.

Another example is ")()())", where the longest valid parentheses substring is "()()", which has length = 4.

int longestValidParentheses(string s) {

    int maxLen = ;

    int lastError = -;

    vector<int> stack;

    for(int i=; i<s.size(); i++)

    {

        if (s[i] == '(')

            stack.push_back(i);

        else if (s[i] == ')')

        {

            if (stack.size()> )

            {

                stack.pop_back();

                int len;

                if (stack.size()==)

                    len = i - lastError;

                else

                    len = i - stack.back();

                if (len > maxLen)

                    maxLen = len;

            }

            else

                lastError = i;

        }

    }

    return maxLen;

}

巴特西

32. Longest Valid Parentheses HARD

最新文章

热门文章