leetcode[20]Valid Parentheses

括号匹配有效性判断

最新推荐文章于 2022-01-09 05:17:54 发布

转载最新推荐文章于 2022-01-09 05:17:54 发布 · 52 阅读

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原文链接：http://www.cnblogs.com/Vae1990Silence/p/4283667.html

本文介绍了一种使用栈数据结构来验证包含括号的字符串是否有效的算法。该算法能够检查括号是否正确配对，例如'()'和'()[]{}

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.

class Solution {
public:
    bool isValid(string s) {
       if(s.size()%2)return false;
       stack<char> stackS;
       for(int i=0;i<s.size();i++)
       {
           if(s[i]=='('||s[i]=='['||s[i]=='{')
           stackS.push(s[i]);
           if(s[i]==')'||s[i]==']'||s[i]=='}')
           {
               if(!stackS.empty())
               {
                    if(((stackS.top()=='(')&&(s[i]!=')'))||((stackS.top()=='[')&&(s[i]!=']'))||((stackS.top()=='{')&&(s[i]!='}')))
                    {
                        stackS.pop();
                        return false;
                    }
                        stackS.pop();
               }
               else
                  return false;
           }
       }
       if(stackS.empty())return true;
       else return false;
    }
};

转载于:https://www.cnblogs.com/Vae1990Silence/p/4283667.html