scusate ancora una cosa..ho ancora un programmino che nn mi risce di far funzionare:
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//point.h
//////////////////////////////////////////////
//Ereditarietà:classi punto e cerchio //
//////////////////////////////////////////////

#include<iostream>


#ifndef POINT_H
#define POINT_H

using namespace std;

class Point{
friend ostream &operator<<(ostream &,const Point &);
public:
Point(int=0,int=0);
GetX();
GetY();
private:
int x;
int y;
};

#endif
---------------------------------------------------------------------------------------
//point.cpp

#include <iomanip>
#include <iostream>

#include "point.h"
//costruttore
Point::Point(int primo,int secondo){
x=primo;
y=secondo;
}

int Point::GetX(){
return x;
}
int Point::GetY(){
return y;
}

ostream &operator<<(ostream &output,Point &p){
output<<"["<<setw(4)<<p.GetX()<<","<<setw(4)<<p.GetY()<< "]\n";
return output;
}
----------------------------------------------------------------------------------------
//circle.h

#ifndef CIRCLE_H
#define CIRCLE_H
#include <iostream>
#include "point.h"
//using namespace std;


class Circle : public Point{
friend ostream &operator<<(ostream &,Circle &);
public:
Circle(double =0.0;int =0,int =0);
double GetRadius();
double Area();
protected:
double radius;
};

#endif
----------------------------------------------------------------------------------------
//circle.cpp
#include "circle.h"
#include "point.h"
#include <iomanip>
#include <iostream>
#define PI 3.14
using namespace std;


Circle::Circle(double r,int x,int y):
Point(x,y){
radius=r;
}
double Circle::GetRadius(){
return radius;
}
double Circle::Area(){
return (radius*radius*PI);
}
ostream &operator<<(ostream &output,Circle &c){
output<<"Il cerchio ha centro: "<<static_cast<Point>(c)<<"\n"
<<"Il raggio del cechio è: "<<c.GetRadius()<<"\n"
<<"L'area è: "<<c.Area()<<endl;
return output;
}
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la classe Point me la compila senza errori..la classe Circle mi da questi errori:
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Compiling...
circle.cpp
c:\documents and settings\emanuele\desktop\array\circle.h(13) : error C2143: syntax error : missing ')' before ';'
c:\documents and settings\emanuele\desktop\array\circle.h(13) : error C2143: syntax error : missing ')' before ';'
c:\documents and settings\emanuele\desktop\array\circle.h(13) : error C2059: syntax error : '='
c:\documents and settings\emanuele\desktop\array\circle.h(13) : error C2059: syntax error : ')'
c:\documents and settings\emanuele\desktop\array\circle.h(13) : error C2238: unexpected token(s) preceding ';'
c:\documents and settings\emanuele\desktop\array\circle.cpp(10) : error C2511: 'Circle::Circle' : overloaded member function 'void (double,int,int)' not found in 'Circle'
c:\documents and settings\emanuele\desktop\array\circle.h(10) : see declaration of 'Circle'
Error executing cl.exe.

circle.obj - 6 error(s), 0 warning(s)
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mi potete aiutare??