import java.util.*;
public class N3 {
public static void main(String[] args)
{
Scanner input=new Scanner(System.in);
int a , b , i;
System.out.print("Please enter a: ");
a=input.nextInt();
System.out.print("Please enter b: ");
b=input.nextInt();

for (i=a ; i <=b ; i=i+3)
System.out.println(i);

}

}