#include<iostream>

using namespace std;

int main()
{
    int line;
    cin >> line;

    char c;
    cin >> c;

    double a[12][12];
    for(int i = 0;i < 12;i ++)
        for(int j = 0;j < 12;j ++) cin >> a[i][j];

    double sum = 0;
    for(int i = 0;i < 12;i ++)
    {
        sum += a[line][i];
    }
    if(c == 'S') printf("%.1lf\n",sum);
    if(c == 'M') printf("%.1lf\n",sum / 12);

    return 0;
}