#include <stdio.h>

int main(void)
{
	int a, b, y, counter;
	while(1){
		counter = 0;
		scanf("%d %d", &a, &b);
		if (a == 0&& b == 0){
			break;
		}
		y = a;
		//printf("%d\n", a);
		for (int i = a; i < b; i++){//	y == i
			if (!(y%400)){
				printf("%d\n", y);
			counter++;
			}else if((!(y%4)) && y%100){
				printf("%d\n", y);
				counter++;
			}
			y++;
		}
		if (counter == 0){
			printf("NA\n");
		}else{
			printf("\n");
		}
	}

	return 0;
}
		
	