lintcode-423

class Solution {
public:
    
    bool isValidParentheses(string& s) {
        // Write your code here
        if(0==s.size()||1==s.size())
            return false;
        stack<char> base;
        for(auto e: s){
            if(e=='('||e=='{'||e=='['){
                base.push(e);
            }else{
                int val=base.top();
                if(e==')'&&val!='('||e=='}'&&val!='{'||e==']'&&val!='['){
                    return false;    
                }
                base.pop();
            }    
        }
        return base.empty()?true:false;
    }
};