import java.math.BigDecimal;
import java.util.*;
import java.util.regex.Pattern;
public class Main {
  public static void main(String[] args){
    new Main().run();
  }
  void run() {
    Scanner sc = new Scanner(System.in);
    BigDecimal A = new BigDecimal(sc.nextDouble());
    BigDecimal B = new BigDecimal(sc.nextDouble());
    String ans = A.multiply(B).toPlainString();
    System.out.println(ans.replaceFirst("\\..*$", ""));
  }
} import java.math.BigDecimal; BigDecimal java.math import java.util.*; util.* java import java.util.regex.Pattern; Pattern java.util.regex public class Main {
  public static void main(String[] args){
    new Main().run();
  }
  void run() {
    Scanner sc = new Scanner(System.in);
    BigDecimal A = new BigDecimal(sc.nextDouble());
    BigDecimal B = new BigDecimal(sc.nextDouble());
    String ans = A.multiply(B).toPlainString();
    System.out.println(ans.replaceFirst("\\..*$", ""));
  }
} Main public static void main(String[] args){
    new Main().run();
  } main {
    new Main().run();
  } new Main().run() new Main().run new Main() String[] args args void run() {
    Scanner sc = new Scanner(System.in);
    BigDecimal A = new BigDecimal(sc.nextDouble());
    BigDecimal B = new BigDecimal(sc.nextDouble());
    String ans = A.multiply(B).toPlainString();
    System.out.println(ans.replaceFirst("\\..*$", ""));
  } run {
    Scanner sc = new Scanner(System.in);
    BigDecimal A = new BigDecimal(sc.nextDouble());
    BigDecimal B = new BigDecimal(sc.nextDouble());
    String ans = A.multiply(B).toPlainString();
    System.out.println(ans.replaceFirst("\\..*$", ""));
  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) BigDecimal A = new BigDecimal(sc.nextDouble()); A new BigDecimal(sc.nextDouble()) BigDecimal B = new BigDecimal(sc.nextDouble()); B new BigDecimal(sc.nextDouble()) String ans = A.multiply(B).toPlainString(); ans A.multiply(B).toPlainString() A.multiply(B).toPlainString A.multiply(B) A.multiply A B System.out.println(ans.replaceFirst("\\..*$", "")) System.out.println System.out System System.out ans.replaceFirst("\\..*$", "") ans.replaceFirst ans "\\..*$" "" public class Main {
  public static void main(String[] args){
    new Main().run();
  }
  void run() {
    Scanner sc = new Scanner(System.in);
    BigDecimal A = new BigDecimal(sc.nextDouble());
    BigDecimal B = new BigDecimal(sc.nextDouble());
    String ans = A.multiply(B).toPlainString();
    System.out.println(ans.replaceFirst("\\..*$", ""));
  }
} public class Main {
  public static void main(String[] args){
    new Main().run();
  }
  void run() {
    Scanner sc = new Scanner(System.in);
    BigDecimal A = new BigDecimal(sc.nextDouble());
    BigDecimal B = new BigDecimal(sc.nextDouble());
    String ans = A.multiply(B).toPlainString();
    System.out.println(ans.replaceFirst("\\..*$", ""));
  }
} Main
import java.math.BigDecimal;
import java.util.*;
import java.util.regex.Pattern;
public class Main {
  public static void main(String[] args){
    new Main().run();
  }
  void run() {
    Scanner sc = new Scanner(System.in);
    BigDecimal A = new BigDecimal(sc.nextDouble());
    BigDecimal B = new BigDecimal(sc.nextDouble());
    String ans = A.multiply(B).toPlainString();
    System.out.println(ans.replaceFirst("\\..*$", ""));
  }
}
