#include 
#include 
using namespace std;

int main() {
    string product;
    cin >> product;
    double cena;
    cin >> cena;
    
    int n;
    cin >> n;
    double danok = 0.18;
    for(int i = 0; i < n; i++) {
        string s;
        cin >> s;
        if(s == product) {
            danok = 0.05;
        }
    }
    cena += (cena * danok);
    printf("%.5lf", cena);
    return 0;
                
}
// NNNNNNNNaN