import java.math.BigDecimal;
import java.util.Scanner;
public class Main {
	public static void main(String[] args)throws Exception{
		Scanner stdIn=new Scanner(System.in);
		String A=stdIn.next();
		String B=stdIn.next();
		BigDecimal a = new BigDecimal(A);
		BigDecimal b = new BigDecimal(B);
		System.out.println(a.multiply(b).setScale(0,java.math.RoundingMode.DOWN));
	}
} import java.math.BigDecimal; BigDecimal java.math import java.util.Scanner; Scanner java.util public class Main {
	public static void main(String[] args)throws Exception{
		Scanner stdIn=new Scanner(System.in);
		String A=stdIn.next();
		String B=stdIn.next();
		BigDecimal a = new BigDecimal(A);
		BigDecimal b = new BigDecimal(B);
		System.out.println(a.multiply(b).setScale(0,java.math.RoundingMode.DOWN));
	}
} Main public static void main(String[] args)throws Exception{
		Scanner stdIn=new Scanner(System.in);
		String A=stdIn.next();
		String B=stdIn.next();
		BigDecimal a = new BigDecimal(A);
		BigDecimal b = new BigDecimal(B);
		System.out.println(a.multiply(b).setScale(0,java.math.RoundingMode.DOWN));
	} main {
		Scanner stdIn=new Scanner(System.in);
		String A=stdIn.next();
		String B=stdIn.next();
		BigDecimal a = new BigDecimal(A);
		BigDecimal b = new BigDecimal(B);
		System.out.println(a.multiply(b).setScale(0,java.math.RoundingMode.DOWN));
	} Scanner stdIn=new Scanner(System.in); stdIn new Scanner(System.in) String A=stdIn.next(); A stdIn.next() stdIn.next stdIn String B=stdIn.next(); B stdIn.next() stdIn.next stdIn BigDecimal a = new BigDecimal(A); a new BigDecimal(A) BigDecimal b = new BigDecimal(B); b new BigDecimal(B) System.out.println(a.multiply(b).setScale(0,java.math.RoundingMode.DOWN)) System.out.println System.out System System.out a.multiply(b).setScale(0,java.math.RoundingMode.DOWN) a.multiply(b).setScale a.multiply(b) a.multiply a b 0 java.math.RoundingMode.DOWN java.math.RoundingMode java.math java java.math java.math.RoundingMode java.math.RoundingMode.DOWN String[] args args public class Main {
	public static void main(String[] args)throws Exception{
		Scanner stdIn=new Scanner(System.in);
		String A=stdIn.next();
		String B=stdIn.next();
		BigDecimal a = new BigDecimal(A);
		BigDecimal b = new BigDecimal(B);
		System.out.println(a.multiply(b).setScale(0,java.math.RoundingMode.DOWN));
	}
} public class Main {
	public static void main(String[] args)throws Exception{
		Scanner stdIn=new Scanner(System.in);
		String A=stdIn.next();
		String B=stdIn.next();
		BigDecimal a = new BigDecimal(A);
		BigDecimal b = new BigDecimal(B);
		System.out.println(a.multiply(b).setScale(0,java.math.RoundingMode.DOWN));
	}
} Main
import java.math.BigDecimal;
import java.util.Scanner;
public class Main {
	public static void main(String[] args)throws Exception{
		Scanner stdIn=new Scanner(System.in);
		String A=stdIn.next();
		String B=stdIn.next();
		BigDecimal a = new BigDecimal(A);
		BigDecimal b = new BigDecimal(B);
		System.out.println(a.multiply(b).setScale(0,java.math.RoundingMode.DOWN));
	}
}
