public class Sisestus3{
   public static void main(String[] a){
      if(a.length==2){
         System.out.println(Arvutused.keskmine(
           Double.parseDouble(a[0]),
           Double.parseDouble(a[1])
         ));
      }
      if(a.length>2){
         double[] arvud=new double[a.length];
         for(int i=0; i<a.length; i++){
            arvud[i]=Double.parseDouble(a[i]);
         }
         System.out.println(Arvutused.keskmine(arvud));
      }
   }
}