public class GCD_LCM {
    public static int gcd(int a, int b) {
        while (b != 0) {
            int temp = b;
            b = a - (a / b) * b;
            a = temp;
        }
        return a;
    }

    public static int lcm(int a, int b) {
        return (a * b) / gcd(a, b);
    }

    public static int main() {
        System.out.println(gcd(48, 18));
        System.out.println(gcd(100, 75));
        System.out.println(gcd(17, 19));

        System.out.println(lcm(12, 18));
        System.out.println(lcm(15, 25));
        System.out.println(lcm(7, 13));
        return 0;
    }
}