import java.math.BigDecimal;
import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        long A = Long.parseLong(scanner.next());
        double B = Double.parseDouble(scanner.next());
        scanner.close();

        BigDecimal num = BigDecimal.valueOf(A);
        num = num.multiply(BigDecimal.valueOf(B));
        num = num.setScale(0, BigDecimal.ROUND_DOWN);

        System.out.println(num.toString());
    }
} import java.math.BigDecimal; BigDecimal java.math import java.util.Scanner; Scanner java.util public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        long A = Long.parseLong(scanner.next());
        double B = Double.parseDouble(scanner.next());
        scanner.close();

        BigDecimal num = BigDecimal.valueOf(A);
        num = num.multiply(BigDecimal.valueOf(B));
        num = num.setScale(0, BigDecimal.ROUND_DOWN);

        System.out.println(num.toString());
    }
} Main public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        long A = Long.parseLong(scanner.next());
        double B = Double.parseDouble(scanner.next());
        scanner.close();

        BigDecimal num = BigDecimal.valueOf(A);
        num = num.multiply(BigDecimal.valueOf(B));
        num = num.setScale(0, BigDecimal.ROUND_DOWN);

        System.out.println(num.toString());
    } main {
        Scanner scanner = new Scanner(System.in);
        long A = Long.parseLong(scanner.next());
        double B = Double.parseDouble(scanner.next());
        scanner.close();

        BigDecimal num = BigDecimal.valueOf(A);
        num = num.multiply(BigDecimal.valueOf(B));
        num = num.setScale(0, BigDecimal.ROUND_DOWN);

        System.out.println(num.toString());
    } Scanner scanner = new Scanner(System.in); scanner new Scanner(System.in) long A = Long.parseLong(scanner.next()); A Long.parseLong(scanner.next()) Long.parseLong Long scanner.next() scanner.next scanner double B = Double.parseDouble(scanner.next()); B Double.parseDouble(scanner.next()) Double.parseDouble Double scanner.next() scanner.next scanner scanner.close() scanner.close scanner BigDecimal num = BigDecimal.valueOf(A); num BigDecimal.valueOf(A) BigDecimal.valueOf BigDecimal A num = num.multiply(BigDecimal.valueOf(B)) num num.multiply(BigDecimal.valueOf(B)) num.multiply num BigDecimal.valueOf(B) BigDecimal.valueOf BigDecimal B num = num.setScale(0, BigDecimal.ROUND_DOWN) num num.setScale(0, BigDecimal.ROUND_DOWN) num.setScale num 0 BigDecimal.ROUND_DOWN BigDecimal BigDecimal.ROUND_DOWN System.out.println(num.toString()) System.out.println System.out System System.out num.toString() num.toString num String[] args args public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        long A = Long.parseLong(scanner.next());
        double B = Double.parseDouble(scanner.next());
        scanner.close();

        BigDecimal num = BigDecimal.valueOf(A);
        num = num.multiply(BigDecimal.valueOf(B));
        num = num.setScale(0, BigDecimal.ROUND_DOWN);

        System.out.println(num.toString());
    }
} public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        long A = Long.parseLong(scanner.next());
        double B = Double.parseDouble(scanner.next());
        scanner.close();

        BigDecimal num = BigDecimal.valueOf(A);
        num = num.multiply(BigDecimal.valueOf(B));
        num = num.setScale(0, BigDecimal.ROUND_DOWN);

        System.out.println(num.toString());
    }
} Main
import java.math.BigDecimal;
import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        long A = Long.parseLong(scanner.next());
        double B = Double.parseDouble(scanner.next());
        scanner.close();

        BigDecimal num = BigDecimal.valueOf(A);
        num = num.multiply(BigDecimal.valueOf(B));
        num = num.setScale(0, BigDecimal.ROUND_DOWN);

        System.out.println(num.toString());
    }
}
