682. Baseball Game

 static int wing=[]()
 {
     std::ios::sync_with_stdio(false);
     cin.tie(NULL);
     return ;
 }();

 class Solution
 {
 public:
     int calPoints(vector<string>& ops)
     {
         int lastvalid=;
         int sz=ops.size();
         vector<int> sore(sz+,INT_MIN);
         for(string &s:ops)
         {
             if(s[]=='+')
             {
                 sore[lastvalid]=sore[lastvalid-]+sore[lastvalid-];
                 lastvalid++;
             }
             else if(s[]=='D')
             {
                 sore[lastvalid]=sore[lastvalid-]*;
                 lastvalid++;
             }
             else if(s[]=='C')
                 lastvalid--;
             else
                 sore[lastvalid++]=stoi(s);
         }
         return accumulate(sore.begin(),sore.begin()+lastvalid,);
     }
 };

用栈或者vector都行，string转int可以直接stoi，学到了，妈个腿