标签:style blog color os io for ar div log
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.
方法:用stack<char> 进行配对即可。
class Solution { public: bool isValid(string s) { int len = s.size(); if(len==0) return true; else if(s[0]==‘)‘|| s[0]==‘]‘|| s[0]==‘}‘) return false; stack<char> st; for(int i=0;i<len;i++){ if(st.empty()){ st.push(s[i]); }else if((s[i]==‘}‘ && st.top()!=‘{‘)||(s[i]==‘)‘ && st.top()!=‘(‘)||(s[i]==‘]‘ && st.top()!=‘[‘)){ return false; }else if((s[i]==‘}‘ && st.top()==‘{‘)||(s[i]==‘)‘ && st.top()==‘(‘)||(s[i]==‘]‘ && st.top()==‘[‘)){ st.pop(); }else{ st.push(s[i]); } }//end for if(st.empty()) return true; else return false; }//end func };
标签:style blog color os io for ar div log
原文地址:http://www.cnblogs.com/Xylophone/p/3934565.html