import java.util.*; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int m = sc.nextInt(); int n = sc.nextInt(); int result = getCM(m, n); System.out.println(result); } public static int getCM(int m, int n){ int max=Math.max(m,n); for (int i = max; i <= m*n; i++) { if(i%m==0&&i%n==0){ return i; } } return -1; } }