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

public class Main {
    public static void main(String[] args) {
        FastReader sc = new FastReader();
        int first = sc.nextInt();
        int second = sc.nextInt();
        int mod_fist = first%2019;
        int mod_second = second%2019;
        int ans = 2018;
        if (first+2020<=second) {
            ans = 0;
        }
        for (int i=mod_fist; i<=mod_second; i++) {
            for (int j=i+1; j<=mod_second; j++) {
                ans = Math.min(ans, (i*j)%2019);
            }
        }
        System.out.println(ans);
    }
    static class FastReader
    {
        BufferedReader br;
        StringTokenizer st;

        public FastReader()
        {
            br = new BufferedReader(new
                    InputStreamReader(System.in));
        }

        String next()
        {
            while (st == null || !st.hasMoreElements())
            {
                try
                {
                    st = new StringTokenizer(br.readLine());
                }
                catch (IOException e)
                {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt()
        {
            return Integer.parseInt(next());
        }

        long nextLong()
        {
            return Long.parseLong(next());
        }

        double nextDouble()
        {
            return Double.parseDouble(next());
        }

        String nextLine()
        {
            String str = "";
            try
            {
                str = br.readLine();
            }
            catch (IOException e)
            {
                e.printStackTrace();
            }
            return str;
        }
    }
} import java.io.BufferedReader; BufferedReader java.io import java.io.IOException; IOException java.io import java.io.InputStreamReader; InputStreamReader java.io import java.util.StringTokenizer; StringTokenizer java.util public class Main {
    public static void main(String[] args) {
        FastReader sc = new FastReader();
        int first = sc.nextInt();
        int second = sc.nextInt();
        int mod_fist = first%2019;
        int mod_second = second%2019;
        int ans = 2018;
        if (first+2020<=second) {
            ans = 0;
        }
        for (int i=mod_fist; i<=mod_second; i++) {
            for (int j=i+1; j<=mod_second; j++) {
                ans = Math.min(ans, (i*j)%2019);
            }
        }
        System.out.println(ans);
    }
    static class FastReader
    {
        BufferedReader br;
        StringTokenizer st;

        public FastReader()
        {
            br = new BufferedReader(new
                    InputStreamReader(System.in));
        }

        String next()
        {
            while (st == null || !st.hasMoreElements())
            {
                try
                {
                    st = new StringTokenizer(br.readLine());
                }
                catch (IOException e)
                {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt()
        {
            return Integer.parseInt(next());
        }

        long nextLong()
        {
            return Long.parseLong(next());
        }

        double nextDouble()
        {
            return Double.parseDouble(next());
        }

        String nextLine()
        {
            String str = "";
            try
            {
                str = br.readLine();
            }
            catch (IOException e)
            {
                e.printStackTrace();
            }
            return str;
        }
    }
} Main public static void main(String[] args) {
        FastReader sc = new FastReader();
        int first = sc.nextInt();
        int second = sc.nextInt();
        int mod_fist = first%2019;
        int mod_second = second%2019;
        int ans = 2018;
        if (first+2020<=second) {
            ans = 0;
        }
        for (int i=mod_fist; i<=mod_second; i++) {
            for (int j=i+1; j<=mod_second; j++) {
                ans = Math.min(ans, (i*j)%2019);
            }
        }
        System.out.println(ans);
    } main {
        FastReader sc = new FastReader();
        int first = sc.nextInt();
        int second = sc.nextInt();
        int mod_fist = first%2019;
        int mod_second = second%2019;
        int ans = 2018;
        if (first+2020<=second) {
            ans = 0;
        }
        for (int i=mod_fist; i<=mod_second; i++) {
            for (int j=i+1; j<=mod_second; j++) {
                ans = Math.min(ans, (i*j)%2019);
            }
        }
        System.out.println(ans);
    } FastReader sc = new FastReader(); sc new FastReader() int first = sc.nextInt(); first sc.nextInt() sc.nextInt sc int second = sc.nextInt(); second sc.nextInt() sc.nextInt sc int mod_fist = first%2019; mod_fist first%2019 first 2019 int mod_second = second%2019; mod_second second%2019 second 2019 int ans = 2018; ans 2018 if (first+2020<=second) {
            ans = 0;
        } first+2020<=second first+2020 first 2020 second {
            ans = 0;
        } ans = 0 ans 0 for (int i=mod_fist; i<=mod_second; i++) {
            for (int j=i+1; j<=mod_second; j++) {
                ans = Math.min(ans, (i*j)%2019);
            }
        } int i=mod_fist; int i=mod_fist; i mod_fist i<=mod_second i mod_second i++ i++ i {
            for (int j=i+1; j<=mod_second; j++) {
                ans = Math.min(ans, (i*j)%2019);
            }
        } {
            for (int j=i+1; j<=mod_second; j++) {
                ans = Math.min(ans, (i*j)%2019);
            }
        } for (int j=i+1; j<=mod_second; j++) {
                ans = Math.min(ans, (i*j)%2019);
            } int j=i+1; int j=i+1; j i+1 i 1 j<=mod_second j mod_second j++ j++ j {
                ans = Math.min(ans, (i*j)%2019);
            } {
                ans = Math.min(ans, (i*j)%2019);
            } ans = Math.min(ans, (i*j)%2019) ans Math.min(ans, (i*j)%2019) Math.min Math ans (i*j)%2019 (i*j) i j 2019 System.out.println(ans) System.out.println System.out System System.out ans String[] args args static class FastReader
    {
        BufferedReader br;
        StringTokenizer st;

        public FastReader()
        {
            br = new BufferedReader(new
                    InputStreamReader(System.in));
        }

        String next()
        {
            while (st == null || !st.hasMoreElements())
            {
                try
                {
                    st = new StringTokenizer(br.readLine());
                }
                catch (IOException e)
                {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt()
        {
            return Integer.parseInt(next());
        }

        long nextLong()
        {
            return Long.parseLong(next());
        }

        double nextDouble()
        {
            return Double.parseDouble(next());
        }

        String nextLine()
        {
            String str = "";
            try
            {
                str = br.readLine();
            }
            catch (IOException e)
            {
                e.printStackTrace();
            }
            return str;
        }
    } FastReader BufferedReader br; br StringTokenizer st; st public FastReader()
        {
            br = new BufferedReader(new
                    InputStreamReader(System.in));
        } FastReader {
            br = new BufferedReader(new
                    InputStreamReader(System.in));
        } br = new BufferedReader(new
                    InputStreamReader(System.in)) br new BufferedReader(new
                    InputStreamReader(System.in)) String next()
        {
            while (st == null || !st.hasMoreElements())
            {
                try
                {
                    st = new StringTokenizer(br.readLine());
                }
                catch (IOException e)
                {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        } next {
            while (st == null || !st.hasMoreElements())
            {
                try
                {
                    st = new StringTokenizer(br.readLine());
                }
                catch (IOException e)
                {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        } while (st == null || !st.hasMoreElements())
            {
                try
                {
                    st = new StringTokenizer(br.readLine());
                }
                catch (IOException e)
                {
                    e.printStackTrace();
                }
            } st == null || !st.hasMoreElements() st == null st null !st.hasMoreElements() st.hasMoreElements() st.hasMoreElements st {
                try
                {
                    st = new StringTokenizer(br.readLine());
                }
                catch (IOException e)
                {
                    e.printStackTrace();
                }
            } try
                {
                    st = new StringTokenizer(br.readLine());
                }
                catch (IOException e)
                {
                    e.printStackTrace();
                } catch (IOException e)
                {
                    e.printStackTrace();
                } IOException e {
                    e.printStackTrace();
                } e.printStackTrace() e.printStackTrace e {
                    st = new StringTokenizer(br.readLine());
                } st = new StringTokenizer(br.readLine()) st new StringTokenizer(br.readLine()) return st.nextToken(); st.nextToken() st.nextToken st int nextInt()
        {
            return Integer.parseInt(next());
        } nextInt {
            return Integer.parseInt(next());
        } return Integer.parseInt(next()); Integer.parseInt(next()) Integer.parseInt Integer next() next long nextLong()
        {
            return Long.parseLong(next());
        } nextLong {
            return Long.parseLong(next());
        } return Long.parseLong(next()); Long.parseLong(next()) Long.parseLong Long next() next double nextDouble()
        {
            return Double.parseDouble(next());
        } nextDouble {
            return Double.parseDouble(next());
        } return Double.parseDouble(next()); Double.parseDouble(next()) Double.parseDouble Double next() next String nextLine()
        {
            String str = "";
            try
            {
                str = br.readLine();
            }
            catch (IOException e)
            {
                e.printStackTrace();
            }
            return str;
        } nextLine {
            String str = "";
            try
            {
                str = br.readLine();
            }
            catch (IOException e)
            {
                e.printStackTrace();
            }
            return str;
        } String str = ""; str "" try
            {
                str = br.readLine();
            }
            catch (IOException e)
            {
                e.printStackTrace();
            } catch (IOException e)
            {
                e.printStackTrace();
            } IOException e {
                e.printStackTrace();
            } e.printStackTrace() e.printStackTrace e {
                str = br.readLine();
            } str = br.readLine() str br.readLine() br.readLine br return str; str public class Main {
    public static void main(String[] args) {
        FastReader sc = new FastReader();
        int first = sc.nextInt();
        int second = sc.nextInt();
        int mod_fist = first%2019;
        int mod_second = second%2019;
        int ans = 2018;
        if (first+2020<=second) {
            ans = 0;
        }
        for (int i=mod_fist; i<=mod_second; i++) {
            for (int j=i+1; j<=mod_second; j++) {
                ans = Math.min(ans, (i*j)%2019);
            }
        }
        System.out.println(ans);
    }
    static class FastReader
    {
        BufferedReader br;
        StringTokenizer st;

        public FastReader()
        {
            br = new BufferedReader(new
                    InputStreamReader(System.in));
        }

        String next()
        {
            while (st == null || !st.hasMoreElements())
            {
                try
                {
                    st = new StringTokenizer(br.readLine());
                }
                catch (IOException e)
                {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt()
        {
            return Integer.parseInt(next());
        }

        long nextLong()
        {
            return Long.parseLong(next());
        }

        double nextDouble()
        {
            return Double.parseDouble(next());
        }

        String nextLine()
        {
            String str = "";
            try
            {
                str = br.readLine();
            }
            catch (IOException e)
            {
                e.printStackTrace();
            }
            return str;
        }
    }
} public class Main {
    public static void main(String[] args) {
        FastReader sc = new FastReader();
        int first = sc.nextInt();
        int second = sc.nextInt();
        int mod_fist = first%2019;
        int mod_second = second%2019;
        int ans = 2018;
        if (first+2020<=second) {
            ans = 0;
        }
        for (int i=mod_fist; i<=mod_second; i++) {
            for (int j=i+1; j<=mod_second; j++) {
                ans = Math.min(ans, (i*j)%2019);
            }
        }
        System.out.println(ans);
    }
    static class FastReader
    {
        BufferedReader br;
        StringTokenizer st;

        public FastReader()
        {
            br = new BufferedReader(new
                    InputStreamReader(System.in));
        }

        String next()
        {
            while (st == null || !st.hasMoreElements())
            {
                try
                {
                    st = new StringTokenizer(br.readLine());
                }
                catch (IOException e)
                {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt()
        {
            return Integer.parseInt(next());
        }

        long nextLong()
        {
            return Long.parseLong(next());
        }

        double nextDouble()
        {
            return Double.parseDouble(next());
        }

        String nextLine()
        {
            String str = "";
            try
            {
                str = br.readLine();
            }
            catch (IOException e)
            {
                e.printStackTrace();
            }
            return str;
        }
    }
} Main
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.StringTokenizer;

public class Main {
    public static void main(String[] args) {
        FastReader sc = new FastReader();
        int first = sc.nextInt();
        int second = sc.nextInt();
        int mod_fist = first%2019;
        int mod_second = second%2019;
        int ans = 2018;
        if (first+2020<=second) {
            ans = 0;
        }
        for (int i=mod_fist; i<=mod_second; i++) {
            for (int j=i+1; j<=mod_second; j++) {
                ans = Math.min(ans, (i*j)%2019);
            }
        }
        System.out.println(ans);
    }
    static class FastReader
    {
        BufferedReader br;
        StringTokenizer st;

        public FastReader()
        {
            br = new BufferedReader(new
                    InputStreamReader(System.in));
        }

        String next()
        {
            while (st == null || !st.hasMoreElements())
            {
                try
                {
                    st = new StringTokenizer(br.readLine());
                }
                catch (IOException e)
                {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt()
        {
            return Integer.parseInt(next());
        }

        long nextLong()
        {
            return Long.parseLong(next());
        }

        double nextDouble()
        {
            return Double.parseDouble(next());
        }

        String nextLine()
        {
            String str = "";
            try
            {
                str = br.readLine();
            }
            catch (IOException e)
            {
                e.printStackTrace();
            }
            return str;
        }
    }
}
