标签：
https://leetcode.com/problems/valid-parentheses/
原题：
Given a string containing just the characters ‘(‘, ‘)‘, ‘{‘, ‘}‘, ‘[‘ and ‘]‘, determine if the input string is valid.
The brackets must close in the correct order, "()" and "()[]{}" are all valid but "(]" and "([)]" are not.
思路:
考察stack的应用。
我的AC代码:
1 class Solution { 2 public: 3 bool isValid(string s) { 4 int n=s.size(); 5 if(n%2==1) 6 return false; 7 stack<char> a; //push,pop,top,size 8 for(int i=0;i<n;i++){ 9 if(s[i]==‘(‘|| s[i]==‘[‘||s[i]==‘{‘) 10 a.push(s[i]); 11 else if (a.empty()==false &&( (a.top()==‘(‘ && s[i]==‘)‘) || (a.top()==‘[‘ && s[i]==‘]‘) || (a.top()==‘{‘ && s[i]==‘}‘) ) ) 12 a.pop(); 13 else 14 return false; 15 } 16 if(a.empty()) 17 return true; 18 else return false; 19 } 20 };
LeetCode(20)--Valid Parentheses
标签：
原文地址：http://www.cnblogs.com/aezero/p/4558532.html
