Tyvj——P1952 Easy

 1 #include <cstdio>
 2 
 3 const int N(233333);
 4 double ans,comb;
 5 char s[N];
 6 
 7 int Presist()
 8 {
 9     int n; scanf("%d",&n);
10     scanf("%s",s);
11     for(int i=0; i<n; ++i)
12     {
13         if(s[i]==‘x‘) comb=0;
14         else if(s[i]==‘o‘)
15             ++comb,ans+=comb+comb-1;
16         else ans+=comb+0.5,comb=(comb+1)/2;
17     }
18     printf("%.4lf",ans);
19     return 0;
20 }
21 
22 int Aptal=Presist();
23 int main(int argc,char**argv){;}