zoj 1048

 1 #include<iostream>
 2 #include<cmath>
 3 #include<iomanip>
 4 using namespace std;
 5 
 6 int main()
 7 {
 8           double a[10000];
 9           int i = 0;
10           double sum = 0;
11           for(i = 0;i<12;i++)
12           {
13                     cin>>a[i];
14                     sum+=a[i];
15           }
16           cout<<fixed<<setprecision(2)<<"$"<<sum/12<<endl;
17 }