#include <stdio.h>
#include <algorithm>
#include <deque>
using namespace std;
using ll = long long;

//207
int main() {
	int A, B;
	scanf("%d %d", &A, &B);

	if (A % 3 != 0)
		A += 3 - A % 3;

	for (int i = A; i < B; i += 3)
		printf("%d\n", i);
}