import java.util.Scanner;
public class Main{
public static void main (String[] args) {
Scanner obj = new Scanner(System.in);
double M[][] = new double[12][12];
double sum = 0.0;
int i,j,counter = 1;
String O = obj.next();
for(i = 0; i < 12; i++){
for(j = 0; j < 12; j++){
M[i][j] = obj.nextDouble();
}
}
for(i = 10; i >= 0; i--){
for(j = 0; j < counter; j++){
sum += M[i][j];
}
counter++;
}
if(O.equals("S")){
System.out.printf("%.1f
", sum);
}else if(O.equals("M")){
System.out.printf("%.1f
", sum/66.0);
}
}
}