import java .util.Scanner;
public class LoanInterestCalculator {
    public static void main(String args[]){
        Scanner sc = new Scanner(System.in);
        int principal = sc.nextInt();
        int term = sc.nextInt();
        if(principal <0) {
             System.out.println("Invalid input");
        }
        if(term < 1) {
            System.out.println("Invalid input");
        } else {
            double rate = 0.05;
            double time = term/12.0;
            double Interest = Principal*Rate*Time;
            System.out.printf("%.2f%n",interest);
        }
        sc.close();
    }
}