```cpp

include[HTML_REMOVED]

include[HTML_REMOVED]

using namespace std;
double a[12][12];
int main(){
double sum=0,c=0;
char ch;

cin>>ch;
for(int i=0;i<12;i++){
    for(int j=0;j<12;j++){
        cin>>a[i][j];
    }
}
for(int i=1;i<12;i++){
    for(int j=0;j<i;j++){
        sum+=a[i][j];
        c++;
    }
}
if(ch=='S') printf("%.1lf",sum);
else if(ch=='M') printf("%.1lf",sum/c);
return 0;

}