import java.util.Scanner;
public class Main{
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    int l = sc.nextInt();
    int r = sc.nextInt();
    long ans = 2020;

    r = Math.min(r, l+2019*2);

    for(long i=l; i<=r; ++i) {
      for(long j=i+1; j<=r; ++j) {
        ans = Math.min(ans, i*j%2019);
      }
    }
    System.out.println(ans);
  }
} import java.util.Scanner; Scanner java.util public class Main{
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    int l = sc.nextInt();
    int r = sc.nextInt();
    long ans = 2020;

    r = Math.min(r, l+2019*2);

    for(long i=l; i<=r; ++i) {
      for(long j=i+1; j<=r; ++j) {
        ans = Math.min(ans, i*j%2019);
      }
    }
    System.out.println(ans);
  }
} Main public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    int l = sc.nextInt();
    int r = sc.nextInt();
    long ans = 2020;

    r = Math.min(r, l+2019*2);

    for(long i=l; i<=r; ++i) {
      for(long j=i+1; j<=r; ++j) {
        ans = Math.min(ans, i*j%2019);
      }
    }
    System.out.println(ans);
  } main {
    Scanner sc = new Scanner(System.in);
    int l = sc.nextInt();
    int r = sc.nextInt();
    long ans = 2020;

    r = Math.min(r, l+2019*2);

    for(long i=l; i<=r; ++i) {
      for(long j=i+1; j<=r; ++j) {
        ans = Math.min(ans, i*j%2019);
      }
    }
    System.out.println(ans);
  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int l = sc.nextInt(); l sc.nextInt() sc.nextInt sc int r = sc.nextInt(); r sc.nextInt() sc.nextInt sc long ans = 2020; ans 2020 r = Math.min(r, l+2019*2) r Math.min(r, l+2019*2) Math.min Math r l+2019*2 l 2019*2 2019 2 for(long i=l; i<=r; ++i) {
      for(long j=i+1; j<=r; ++j) {
        ans = Math.min(ans, i*j%2019);
      }
    } long i=l; long i=l; i l i<=r i r ++i ++i i {
      for(long j=i+1; j<=r; ++j) {
        ans = Math.min(ans, i*j%2019);
      }
    } {
      for(long j=i+1; j<=r; ++j) {
        ans = Math.min(ans, i*j%2019);
      }
    } for(long j=i+1; j<=r; ++j) {
        ans = Math.min(ans, i*j%2019);
      } long j=i+1; long j=i+1; j i+1 i 1 j<=r j r ++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 public class Main{
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    int l = sc.nextInt();
    int r = sc.nextInt();
    long ans = 2020;

    r = Math.min(r, l+2019*2);

    for(long i=l; i<=r; ++i) {
      for(long j=i+1; j<=r; ++j) {
        ans = Math.min(ans, i*j%2019);
      }
    }
    System.out.println(ans);
  }
} public class Main{
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    int l = sc.nextInt();
    int r = sc.nextInt();
    long ans = 2020;

    r = Math.min(r, l+2019*2);

    for(long i=l; i<=r; ++i) {
      for(long j=i+1; j<=r; ++j) {
        ans = Math.min(ans, i*j%2019);
      }
    }
    System.out.println(ans);
  }
} Main
import java.util.Scanner;
public class Main{
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    int l = sc.nextInt();
    int r = sc.nextInt();
    long ans = 2020;

    r = Math.min(r, l+2019*2);

    for(long i=l; i<=r; ++i) {
      for(long j=i+1; j<=r; ++j) {
        ans = Math.min(ans, i*j%2019);
      }
    }
    System.out.println(ans);
  }
}