package Maths;

/** @author https://github.com/shellhub/ */

public class GCDRecursion {

public static void main(String[] args) {

System.out.println(gcd(20, 15)); /* output: 5 */

System.out.println(gcd(10, 8)); /* output: 2 */

System.out.println(gcd(gcd(10, 5), gcd(5, 10))); /* output: 5 */

}

/**

* get greatest common divisor

*

* @param a the first number

* @param b the second number

* @return gcd

*/

public static int gcd(int a, int b) {

if (a < 0 || b < 0) {

throw new ArithmeticException();

}

if (a == 0 || b == 0) {

return Math.abs(a - b);

}

if (a % b == 0) {

return b;

} else {

return gcd(b, a % b);

}

}

}