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

public class Main {

    public Main() {
        Scanner scanner = new Scanner(System.in);
        BigDecimal A = new BigDecimal(scanner.next());
        BigDecimal B = new BigDecimal(scanner.next());

        System.out.println(A.multiply(B).longValue());
    }

    public static void main(String[] args) {
        new Main();
    }
} import java.math.BigDecimal; BigDecimal java.math import java.util.Scanner; Scanner java.util public class Main {

    public Main() {
        Scanner scanner = new Scanner(System.in);
        BigDecimal A = new BigDecimal(scanner.next());
        BigDecimal B = new BigDecimal(scanner.next());

        System.out.println(A.multiply(B).longValue());
    }

    public static void main(String[] args) {
        new Main();
    }
} Main public Main() {
        Scanner scanner = new Scanner(System.in);
        BigDecimal A = new BigDecimal(scanner.next());
        BigDecimal B = new BigDecimal(scanner.next());

        System.out.println(A.multiply(B).longValue());
    } Main {
        Scanner scanner = new Scanner(System.in);
        BigDecimal A = new BigDecimal(scanner.next());
        BigDecimal B = new BigDecimal(scanner.next());

        System.out.println(A.multiply(B).longValue());
    } Scanner scanner = new Scanner(System.in); scanner new Scanner(System.in) BigDecimal A = new BigDecimal(scanner.next()); A new BigDecimal(scanner.next()) BigDecimal B = new BigDecimal(scanner.next()); B new BigDecimal(scanner.next()) System.out.println(A.multiply(B).longValue()) System.out.println System.out System System.out A.multiply(B).longValue() A.multiply(B).longValue A.multiply(B) A.multiply A B public static void main(String[] args) {
        new Main();
    } main {
        new Main();
    } new Main() String[] args args public class Main {

    public Main() {
        Scanner scanner = new Scanner(System.in);
        BigDecimal A = new BigDecimal(scanner.next());
        BigDecimal B = new BigDecimal(scanner.next());

        System.out.println(A.multiply(B).longValue());
    }

    public static void main(String[] args) {
        new Main();
    }
} public class Main {

    public Main() {
        Scanner scanner = new Scanner(System.in);
        BigDecimal A = new BigDecimal(scanner.next());
        BigDecimal B = new BigDecimal(scanner.next());

        System.out.println(A.multiply(B).longValue());
    }

    public static void main(String[] args) {
        new Main();
    }
} Main
import java.math.BigDecimal;
import java.util.Scanner;

public class Main {

    public Main() {
        Scanner scanner = new Scanner(System.in);
        BigDecimal A = new BigDecimal(scanner.next());
        BigDecimal B = new BigDecimal(scanner.next());

        System.out.println(A.multiply(B).longValue());
    }

    public static void main(String[] args) {
        new Main();
    }
}
