import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.math.BigDecimal;
import java.util.StringTokenizer;

public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st = new StringTokenizer(in.readLine());
        BigDecimal a = new BigDecimal(st.nextToken());
        BigDecimal b = new BigDecimal(st.nextToken());
        BigDecimal mul = a.multiply(b);
        st = new StringTokenizer(mul.toString(), ".");
        System.out.println(st.nextElement());
    }
} import java.io.BufferedReader; BufferedReader java.io import java.io.IOException; IOException java.io import java.io.InputStreamReader; InputStreamReader java.io import java.math.BigDecimal; BigDecimal java.math import java.util.StringTokenizer; StringTokenizer java.util public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st = new StringTokenizer(in.readLine());
        BigDecimal a = new BigDecimal(st.nextToken());
        BigDecimal b = new BigDecimal(st.nextToken());
        BigDecimal mul = a.multiply(b);
        st = new StringTokenizer(mul.toString(), ".");
        System.out.println(st.nextElement());
    }
} Main public static void main(String[] args) throws IOException {
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st = new StringTokenizer(in.readLine());
        BigDecimal a = new BigDecimal(st.nextToken());
        BigDecimal b = new BigDecimal(st.nextToken());
        BigDecimal mul = a.multiply(b);
        st = new StringTokenizer(mul.toString(), ".");
        System.out.println(st.nextElement());
    } main {
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st = new StringTokenizer(in.readLine());
        BigDecimal a = new BigDecimal(st.nextToken());
        BigDecimal b = new BigDecimal(st.nextToken());
        BigDecimal mul = a.multiply(b);
        st = new StringTokenizer(mul.toString(), ".");
        System.out.println(st.nextElement());
    } BufferedReader in = new BufferedReader(new InputStreamReader(System.in)); in new BufferedReader(new InputStreamReader(System.in)) StringTokenizer st = new StringTokenizer(in.readLine()); st new StringTokenizer(in.readLine()) BigDecimal a = new BigDecimal(st.nextToken()); a new BigDecimal(st.nextToken()) BigDecimal b = new BigDecimal(st.nextToken()); b new BigDecimal(st.nextToken()) BigDecimal mul = a.multiply(b); mul a.multiply(b) a.multiply a b st = new StringTokenizer(mul.toString(), ".") st new StringTokenizer(mul.toString(), ".") System.out.println(st.nextElement()) System.out.println System.out System System.out st.nextElement() st.nextElement st String[] args args public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st = new StringTokenizer(in.readLine());
        BigDecimal a = new BigDecimal(st.nextToken());
        BigDecimal b = new BigDecimal(st.nextToken());
        BigDecimal mul = a.multiply(b);
        st = new StringTokenizer(mul.toString(), ".");
        System.out.println(st.nextElement());
    }
} public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st = new StringTokenizer(in.readLine());
        BigDecimal a = new BigDecimal(st.nextToken());
        BigDecimal b = new BigDecimal(st.nextToken());
        BigDecimal mul = a.multiply(b);
        st = new StringTokenizer(mul.toString(), ".");
        System.out.println(st.nextElement());
    }
} Main
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.math.BigDecimal;
import java.util.StringTokenizer;

public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st = new StringTokenizer(in.readLine());
        BigDecimal a = new BigDecimal(st.nextToken());
        BigDecimal b = new BigDecimal(st.nextToken());
        BigDecimal mul = a.multiply(b);
        st = new StringTokenizer(mul.toString(), ".");
        System.out.println(st.nextElement());
    }
}
