#include <iostream>

using namespace std;

int main() {
	
	int a,b;
	bool f = false;
	cin >> a >> b;
	for(int i = a; i <= b; i++) {
		if(i % 3 == 0) {
			
			if(!f){
				f = true;
			} else {
				cout << i << endl;
				i += 3;
			}
			
			
		}
	}
	
}