#include <stdio.h>
#include <iostream>
 
using namespace std;
 
void uru(int c, int d) {
    int counter = 0;
 
    for (int i = c; i <= d; i++) {
        if (i % 4 == 0) {
            if (i % 100 == 0) {
                if (i % 400 == 0) {
                    cout << i << endl;
                    counter++;
                } 
            } else {
                cout << i << endl;
                counter++;
            }
        }
    }
    if (counter == 0) {
        cout << "NA" << endl;
    }
    //cout << endl;
    return;
}
 
int main() {
    int a,b;
 	bool flag=false;
    while (cin >> a >> b) {
    	if (a == 0 && b == 0) {
            break;
        }
    	if(flag) cout<<endl;
            uru(a,b);
    	flag=true;
    }
	//cout<<000000<<endl;
    return 0;
}