import java.util.Scanner;

public class Main{
    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        int a=sc.nextInt();
        int b=sc.nextInt();
        int r1,r2,r3,r4,r5,r6,r7,r8,r9;

        for (int i = a; i <=b ; i++) {
            int flag=0;
            for (int j = 2; j <=b; j++){
                if (i%j==0){
                    flag++;
                }
            }
            if (flag==1){
                r1=i%10;
                r2=i/10%10;
                r3=i/100%10;
                r4=i/1000%10;
                r5=i/10000%10;
                r6=i/100000%10;
                r7=i/1000000%10;
                r8=i/10000000%10;
//                r9=i/100000000%10;
                if (i>=5&&i<=11){
                    System.out.println(i);
                }

                if (i>100&&i<1000&&r1==r3){
                        System.out.println(i);
                }
                if (i>1000&&i<10000&&r1==r4&&r2==r3){
                        System.out.println(i);
                }

                if (i>10000&&i<100000&&r1==r5&&r2==r4){
                    System.out.println(i);
                }

                if (i>100000&&i<1000000&&r1==r6&&r2==r5&&r3==r4){
                    System.out.println(i);
                }

                if (i>1000000&&i<10000000&&r1==r7&&r2==r6&&r3==r5){
                    System.out.println(i);
                }

                if (i>10000000&&i<100000000&&r1==r8&&r2==r7&&r3==r6&&r4==r5){
                    System.out.println(i);
                }
            }
        }
    }
}