import java.util.Scanner;
import java.math.BigDecimal;
public class patrick_and_rock{
public static void main(String[] args) {
String s1,s2;
Scanner scanner = new Scanner(System.in);
while(scanner.hasNext()) {
s1 = scanner.next();
s2 = scanner.next();
BigDecimal b1 = new BigDecimal(s1);
BigDecimal b2 = new BigDecimal(s2);
System.out.println(b1.multiply(b2));
}

}
}