Compute GCD using three different methods in Java

Problem:

Compute GCD using three different methods in Java.

Output:

Not applicable.

Solution:

/**--------------------Method 1 ---------------*/
public class gcd_recursion_azzam
{
   public static int gcd(int m, int n, int i ) {
     
       if (m%i ==0 && n %i ==0)
         return i;
       else
         return gcd(m,n,--i);
  }
   
   public static void main(String[] args)
   {
     System.out.println(gcd(10,4,4));
   }
}
/**--------------------Method 2 ---------------*/
public class gcd_recursion_book
{
   public static int gcd(int m, int n) {
     
       if (m % n == 0) 
         return n;
       else if (m < n)
         return gcd(m,n);
       else
         return gcd(n, m%n);
     } 
   
   public static void main(String[] args)
   {
     System.out.println(gcd(10,4));
   }
}
/**--------------------Method 3 ---------------*/
public class gdc_recursion_online
{
   public static int gcd(int a, int b) {
     
       if (b==0) 
         return a;
       else
         return gcd(b, a % b);
     } 
   
   public static void main(String[] args)
   {
     System.out.println(gcd(10,4));
   }
}