Java recursive function to find the gcd of 2 number

Write a Java recursive function which take 2 integer as argument and return the GCD.

Solution:

import java.util.*;
class GCD
{
    public static int gcd(int n1,int n2)
    {
        if(n1==n2)     
        {
            return n1;
        }
        else
        {
            if(n1>n2)
                return gcd(n1-n2,n2);
            else
                return gcd(n1,n2-n1);
        }
    }
    public static void main(String arr[]) 
    {
        Scanner sc=new Scanner(System.in);
        System.out.println("Enter First Number: ");
        int num1=sc.nextInt();
        System.out.println("Enter Second Number: ");
        int num2=sc.nextInt();
        int ans=gcd(num1,num2);
        System.out.println("GCD is "+ans);
    }
}

Enter First Number: 

12

Enter Second Number: 

20

GCD is 4