import java.io.BufferedReader;
import java.io.IOException;
import java.io.PrintWriter;
import java.math.BigDecimal;
import java.math.RoundingMode;
import java.util.StringTokenizer;

public class Main {
    
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new java.io.InputStreamReader(System.in));
        PrintWriter pw = new PrintWriter(System.out);
        StringTokenizer st = new StringTokenizer(br.readLine());

        BigDecimal A_big = new BigDecimal(st.nextToken());
        BigDecimal B_big = new BigDecimal(st.nextToken());

        BigDecimal ans = (A_big.multiply(B_big)).setScale(0, RoundingMode.DOWN);
        // BigDecimal ans_d = (A_big.multiply(B_big));

        pw.println(ans.toPlainString());
        // pw.println(ans_d.toPlainString());
        br.close();
        pw.close();
    }
} import java.io.BufferedReader; BufferedReader java.io import java.io.IOException; IOException java.io import java.io.PrintWriter; PrintWriter java.io import java.math.BigDecimal; BigDecimal java.math import java.math.RoundingMode; RoundingMode java.math import java.util.StringTokenizer; StringTokenizer java.util public class Main {
    
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new java.io.InputStreamReader(System.in));
        PrintWriter pw = new PrintWriter(System.out);
        StringTokenizer st = new StringTokenizer(br.readLine());

        BigDecimal A_big = new BigDecimal(st.nextToken());
        BigDecimal B_big = new BigDecimal(st.nextToken());

        BigDecimal ans = (A_big.multiply(B_big)).setScale(0, RoundingMode.DOWN);
        // BigDecimal ans_d = (A_big.multiply(B_big));

        pw.println(ans.toPlainString());
        // pw.println(ans_d.toPlainString());
        br.close();
        pw.close();
    }
} Main public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new java.io.InputStreamReader(System.in));
        PrintWriter pw = new PrintWriter(System.out);
        StringTokenizer st = new StringTokenizer(br.readLine());

        BigDecimal A_big = new BigDecimal(st.nextToken());
        BigDecimal B_big = new BigDecimal(st.nextToken());

        BigDecimal ans = (A_big.multiply(B_big)).setScale(0, RoundingMode.DOWN);
        // BigDecimal ans_d = (A_big.multiply(B_big));

        pw.println(ans.toPlainString());
        // pw.println(ans_d.toPlainString());
        br.close();
        pw.close();
    } main {
        BufferedReader br = new BufferedReader(new java.io.InputStreamReader(System.in));
        PrintWriter pw = new PrintWriter(System.out);
        StringTokenizer st = new StringTokenizer(br.readLine());

        BigDecimal A_big = new BigDecimal(st.nextToken());
        BigDecimal B_big = new BigDecimal(st.nextToken());

        BigDecimal ans = (A_big.multiply(B_big)).setScale(0, RoundingMode.DOWN);
        // BigDecimal ans_d = (A_big.multiply(B_big));

        pw.println(ans.toPlainString());
        // pw.println(ans_d.toPlainString());
        br.close();
        pw.close();
    } BufferedReader br = new BufferedReader(new java.io.InputStreamReader(System.in)); br new BufferedReader(new java.io.InputStreamReader(System.in)) PrintWriter pw = new PrintWriter(System.out); pw new PrintWriter(System.out) StringTokenizer st = new StringTokenizer(br.readLine()); st new StringTokenizer(br.readLine()) BigDecimal A_big = new BigDecimal(st.nextToken()); A_big new BigDecimal(st.nextToken()) BigDecimal B_big = new BigDecimal(st.nextToken()); B_big new BigDecimal(st.nextToken()) BigDecimal ans = (A_big.multiply(B_big)).setScale(0, RoundingMode.DOWN); ans (A_big.multiply(B_big)).setScale(0, RoundingMode.DOWN) (A_big.multiply(B_big)).setScale (A_big.multiply(B_big)) A_big.multiply A_big B_big 0 RoundingMode.DOWN RoundingMode RoundingMode.DOWN pw.println(ans.toPlainString()) pw.println pw ans.toPlainString() ans.toPlainString ans br.close() br.close br pw.close() pw.close pw String[] args args public class Main {
    
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new java.io.InputStreamReader(System.in));
        PrintWriter pw = new PrintWriter(System.out);
        StringTokenizer st = new StringTokenizer(br.readLine());

        BigDecimal A_big = new BigDecimal(st.nextToken());
        BigDecimal B_big = new BigDecimal(st.nextToken());

        BigDecimal ans = (A_big.multiply(B_big)).setScale(0, RoundingMode.DOWN);
        // BigDecimal ans_d = (A_big.multiply(B_big));

        pw.println(ans.toPlainString());
        // pw.println(ans_d.toPlainString());
        br.close();
        pw.close();
    }
} public class Main {
    
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new java.io.InputStreamReader(System.in));
        PrintWriter pw = new PrintWriter(System.out);
        StringTokenizer st = new StringTokenizer(br.readLine());

        BigDecimal A_big = new BigDecimal(st.nextToken());
        BigDecimal B_big = new BigDecimal(st.nextToken());

        BigDecimal ans = (A_big.multiply(B_big)).setScale(0, RoundingMode.DOWN);
        // BigDecimal ans_d = (A_big.multiply(B_big));

        pw.println(ans.toPlainString());
        // pw.println(ans_d.toPlainString());
        br.close();
        pw.close();
    }
} Main
import java.io.BufferedReader;
import java.io.IOException;
import java.io.PrintWriter;
import java.math.BigDecimal;
import java.math.RoundingMode;
import java.util.StringTokenizer;

public class Main {
    
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new java.io.InputStreamReader(System.in));
        PrintWriter pw = new PrintWriter(System.out);
        StringTokenizer st = new StringTokenizer(br.readLine());

        BigDecimal A_big = new BigDecimal(st.nextToken());
        BigDecimal B_big = new BigDecimal(st.nextToken());

        BigDecimal ans = (A_big.multiply(B_big)).setScale(0, RoundingMode.DOWN);
        // BigDecimal ans_d = (A_big.multiply(B_big));

        pw.println(ans.toPlainString());
        // pw.println(ans_d.toPlainString());
        br.close();
        pw.close();
    }
}