#include<iostream>
using namespace std;
int main(){
    double a[12][12],sum=0;
    char op;
    cin>>op;
    int i,j;
    for(i=0;i<12;i++){
        for(j=0;j<12;j++){
            cin>>a[i][j];
            if(i<j&&i+j<11) sum+=a[i][j];
            }
    }
    printf("%.1lf",op=='S'?sum:sum/30);
    return 0;
}