leetcode simplify path

用vector代替stack

class Solution {
public:
vector<string>v1;
    string simplifyPath(string path) 
    {
        v1.clear();
        string s;    
        string temp;
        for(int i=0;i<path.size();)
        {           
          if(path[i]=='/')
          {
              int j=i+1;
              temp="";
              for(;j<path.size()&&path[j]!='/';j++)
              {
                  if(path[j]=='.'&&path[j+1]=='.')
                 {
                   if(v1.size()!=0)
                   v1.pop_back();
                   j=j+2;
                   break;                                  
                 }
                 temp+=path[j];                 
              }
              if(temp!=""&&temp!=".")v1.push_back(temp);
              i=j;
          }          
        }
        if(v1.size()==0)
        s+='/'; 
        for(int i=0;i<v1.size();i++)
        {
            s=s+'/'+v1[i];
        }   
        return s;
    }
};