va be' questo e' il codice giusto:
codice:
class area{
double base;
double height;


area(double x,double y){
base=x;
height=y;
}

double calcolo(){
return base*height;
}
}
class peso extends area{
double weight;

peso(double x, double y, double z){//mi da un errore qui
super(x,y);
weight=z;
}
}


class demoarea{
public static void main(String args[]){
peso es1=new peso(5,6,7);
System.out.println ("L'area e': "+es1.calcolo());
System.out.println ("Il peso e': "+es1.weight);
}
}