import java.util.Scanner;
public class UseRecursion {
       public static void main(String[] args) {
       Scanner scanner = new Scanner (System.in);       
       System.out.println("write two numbers: ");
       System.out.print("m=");
         int m=scanner.nextInt();
         System.out.print("n=");
          int n=scanner.nextInt();  
        
          System.out.println("GCD:"+ gcd(m,n));
        }
       
         private static int gcd(int m,int n) {

          if(n==0)
            return m;
          else  
            return  gcd(n,m %n);    
    }
}