import java.util.*;
public class Salary {
public static void main(String[] args) {
int hour;
int money;
double sum;
System.out.print("請輸入員工的總工作時間\n");
System.out.print("請輸入員工的時薪");
Scanner console = new Scanner(System.in);
hour = console.nextInt();
money = console.nextInt();
if(hour<=40&&hour>=0) {
sum = hour*money;
System.out.println(sum);
}
else if(hour>40&&hour<=50){
sum = 40*money + (hour-40)*money*1.5;
System.out.println(sum);
}
else if(hour>50) {
sum = 40*money + 10*money*1.5 + (hour-50)*money*2;
System.out.println(sum);
}
}
}