Prak 3 S-Data '' INHERITANCE Dalam C++ ''

#include <cstdlib>
#include <iostream>

using namespace std;
class bilangan{
      friend ostream& operator<<(ostream&, const bilangan&);
      friend istream& operator>>(istream&, bilangan&);
      public:
            bilangan(int a0=0, float b0=0.0):a(a0),b(b0){}
            void banding_int(const bilangan&, const bilangan&);
            bilangan& operator=(const bilangan&);
            bilangan operator+(const bilangan&)const;
            bilangan operator-()const;
      protected:
                int a;
                float b;
    
      };

ostream& operator<<(ostream& out, const bilangan& x){
        out<<"Bagian integer: "<<x.a<<endl;
        out<<"Bagian float: "<<x.b<<endl;
        return out;
        }
      
void bilangan::banding_int(const bilangan& x, const bilangan& y){
    if(x.a>y.a)cout<<x.a<<"::x lebih besar dari"<<y.a<<"::y";
    else cout<<x.a<<"::x lebih kecil dari"<<y.a<<"::y";
    }
  
bilangan& bilangan::operator=(const bilangan& x){
          a=x.a;
          b=x.b;
          return *this;
          }

istream& operator>>(istream& in, bilangan& x){
        cout<<"\nMasukkan bagian integer: ";
        in>>x.a;
        cout<<"Masukkan bagian float: ";
        in>>x.b;
        return in;
        }
      
bilangan bilangan::operator+(const bilangan& x)const{
        bilangan cc;
        cc.a=a+x.a;
        cc.b=b+x.b;
        return cc;
        }
      
bilangan bilangan::operator-()const{
        bilangan x;
        x.a=-a;
        x.b=-b;
        return x;
        }

class bil_char:public bilangan{
      friend ostream& operator<<(ostream&, const bil_char&);
      public:
            bil_char(int a0=0, int b0=0,char ch='x'):bilangan(a0,b0),c(ch){}
      private:
              char c;
            };
          
ostream& operator<<(ostream& out,const bil_char& x){
        out<<"Bagian integer: "<<x.a<<endl;
        out<<"Bagian float: "<<x.b<<endl;
        out<<"Bagian char: "<<x.c<<endl;
        return out;
        }
       
   //     class bil_float:public bilangan{
     //         friend ostream& operator<<(ostream&, const bil_char&);
       //       public:
         //           bil_float()
      
int main(int argc, char *argv[])
{
   
    bilangan s,t(-2,3.14),d;
    cout<<"Nilai awal s\n"<<s;
    cout<<"Nilai awal t dari deklarasi\n"<<t;
    s=t;
    cout<<"Setelah diassign t\n";
    cout<<"Nilai s\n"<<s;
    cout<<"Masukkan nilai-nilai objek d";
    cin>>d;
    cout<<"Setelah d+t=>\n"<<d+t;
    cout<<"Nilai d dinegatifkan\n"<<-d;
    bil_char ss;
    cout<<"Nilai awal ss\n"<<ss;
      
    system("PAUSE");
    return EXIT_SUCCESS;
}