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

public class Main {

	public static void main(String[] args) {
		try (Scanner scanner = new Scanner(System.in)) {
			BigDecimal a = BigDecimal.valueOf(scanner.nextLong());
			BigDecimal b = new BigDecimal(scanner.next());
			System.out.println(a.multiply(b).setScale(0, RoundingMode.FLOOR));
		}
	}
} import java.math.BigDecimal; BigDecimal java.math import java.math.RoundingMode; RoundingMode java.math import java.util.Scanner; Scanner java.util public class Main {

	public static void main(String[] args) {
		try (Scanner scanner = new Scanner(System.in)) {
			BigDecimal a = BigDecimal.valueOf(scanner.nextLong());
			BigDecimal b = new BigDecimal(scanner.next());
			System.out.println(a.multiply(b).setScale(0, RoundingMode.FLOOR));
		}
	}
} Main public static void main(String[] args) {
		try (Scanner scanner = new Scanner(System.in)) {
			BigDecimal a = BigDecimal.valueOf(scanner.nextLong());
			BigDecimal b = new BigDecimal(scanner.next());
			System.out.println(a.multiply(b).setScale(0, RoundingMode.FLOOR));
		}
	} main {
		try (Scanner scanner = new Scanner(System.in)) {
			BigDecimal a = BigDecimal.valueOf(scanner.nextLong());
			BigDecimal b = new BigDecimal(scanner.next());
			System.out.println(a.multiply(b).setScale(0, RoundingMode.FLOOR));
		}
	} try (Scanner scanner = new Scanner(System.in)) {
			BigDecimal a = BigDecimal.valueOf(scanner.nextLong());
			BigDecimal b = new BigDecimal(scanner.next());
			System.out.println(a.multiply(b).setScale(0, RoundingMode.FLOOR));
		} {
			BigDecimal a = BigDecimal.valueOf(scanner.nextLong());
			BigDecimal b = new BigDecimal(scanner.next());
			System.out.println(a.multiply(b).setScale(0, RoundingMode.FLOOR));
		} Scanner scanner = new Scanner(System.in) Scanner scanner = new Scanner(System.in) new Scanner(System.in) BigDecimal a = BigDecimal.valueOf(scanner.nextLong()); a BigDecimal.valueOf(scanner.nextLong()) BigDecimal.valueOf BigDecimal scanner.nextLong() scanner.nextLong scanner BigDecimal b = new BigDecimal(scanner.next()); b new BigDecimal(scanner.next()) System.out.println(a.multiply(b).setScale(0, RoundingMode.FLOOR)) System.out.println System.out System System.out a.multiply(b).setScale(0, RoundingMode.FLOOR) a.multiply(b).setScale a.multiply(b) a.multiply a b 0 RoundingMode.FLOOR RoundingMode RoundingMode.FLOOR String[] args args public class Main {

	public static void main(String[] args) {
		try (Scanner scanner = new Scanner(System.in)) {
			BigDecimal a = BigDecimal.valueOf(scanner.nextLong());
			BigDecimal b = new BigDecimal(scanner.next());
			System.out.println(a.multiply(b).setScale(0, RoundingMode.FLOOR));
		}
	}
} public class Main {

	public static void main(String[] args) {
		try (Scanner scanner = new Scanner(System.in)) {
			BigDecimal a = BigDecimal.valueOf(scanner.nextLong());
			BigDecimal b = new BigDecimal(scanner.next());
			System.out.println(a.multiply(b).setScale(0, RoundingMode.FLOOR));
		}
	}
} Main
import java.math.BigDecimal;
import java.math.RoundingMode;
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		try (Scanner scanner = new Scanner(System.in)) {
			BigDecimal a = BigDecimal.valueOf(scanner.nextLong());
			BigDecimal b = new BigDecimal(scanner.next());
			System.out.println(a.multiply(b).setScale(0, RoundingMode.FLOOR));
		}
	}
}
