标签：
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.
class Solution { public: int longestValidParentheses(string s) { int n=s.size(); if(n==0||n==1)return 0; stack<int> stk; int len=0; for (int i=0;i<s.size();i++) { if(s[i]==‘(‘)stk.push(i); else { if(!stk.empty()&&s[stk.top()]==‘(‘) { stk.pop(); int tenlen=stk.empty()?i+1:i-stk.top(); len=tenlen>len?tenlen:len; } else stk.push(i); } } return len; } };
leetcode[32]Longest Valid Parentheses
标签：
原文地址：http://www.cnblogs.com/Vae98Scilence/p/4283608.html
