asdsad

public class CalculatingMachine {
    public String string;
    public CalculatingMachine(String string){
        this.string = string;
    }
    public String calculate(double x, double y){
        double suma = x + y;
        return string+": "+x+"+"+y+"="+suma;
    }
    public static void printRes(CalculatingMachine[] a, double x, double y){
        for(int i=0; i<a.length; i++){
            System.out.println(a[i].calculate(x,y));
        }
    }
}
//////////////////////////////////////////////////////////////////////////
public class Computer
extends Calculator {
    public Computer(String string){
        super(string);
    }
    public String calculate(double x, double y){
        double iloczyn = x*y, iloraz = x/y;
        return super.calculate(x,y)+"; "+x+"*"+y+"="+iloczyn+"; "+x+"/"+y+"="+iloraz;
    }
}
//////////////////////////////////////////////////////////////////////////
public class Calculator
extends CalculatingMachine {
    public Calculator(String string){
        super(string);
    }
    public String calculate(double x, double y){
        double roznica = x-y ;
     return super.calculate(x,y)+"; "+x+"-"+y+"="+roznica;
    }
}