GCDRecursion.java

packagecom.thealgorithms.maths;

/**
 * @author https://github.com/shellhub/
 */
publicfinalclassGCDRecursion {
privateGCDRecursion() {
 }

publicstaticvoidmain(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
 */
publicstaticintgcd(inta, intb) {
if (a < 0 || b < 0) {
thrownewArithmeticException();
 }

if (a == 0 || b == 0) {
returnMath.abs(a - b);
 }

if (a % b == 0) {
returnb;
 } else {
returngcd(b, a % b);
 }
 }
}