HCF & LCM using recursion

import java.util.*;
class HCF_LCM
{
int HCF(int n,int m,int i)
{
if(i==1)
{
return 1;
}
if(m%i==0&&n%i==0)
return i;
else
return HCF(n,m,--i);
}
int LCM(int n,int m,int i)
{
if(i==(m*n))
return (m*n);
if(i%m==0&&i%n==0)
return i;
else
return LCM(n,m,++i);
}
public static void main (String[] args)
{
HCF_LCM call=new HCF_LCM();
Scanner ob=new Scanner(System.in);
System.out.println("Enter 2 numbers such that first number is greater than second number");
int a=ob.nextInt();
int b=ob.nextInt();
int hcf=call.HCF(a,b,b);
int lcm=call.LCM(a,b,b);
System.out.println("HCF="+hcf+"\nLCM="+lcm);
    }
}