#include <iostream>
#include <vector>
using namespace std;

int gcd(int a, int b) {
	while (a != 0) {
		b = b % a;
		swap(a, b);
	}
	return b;
}

int main() {
	/*ifstream fin("input.txt");
	ofstream fout("output.txt");*/
	int a, b;
	cin >> a >> b;
	if (gcd(a, b) != 1) {
		for (int i = 2; i < 2000000; i++) {
			for (int j = 2; j < 2000000; j++) {
				if (i * j == a * b && ((i != a && j != b) || (j != a && j != b))) {
					if (gcd(i, j) == a) {
						cout << i << " " << j;
						return 0;
					}
				}
			}
		}
	}
	else {
		cout << -1;
	}
}