Untitled

#include <iostream>

using namespace std;

class App {
public:

App(int d=0) { download = d; }
~App(){};
int getDownload() { return download; }
void increaseDownload() { ++download; }

private:
int download;

};


class JJBox:public App{
public:
    
	// default constructor is necessary
	JJBox(int d = 0):App(d){
        song = 5 * getDownload();
    }
    int getsongs(){
        return song;
    }
    void update(){
        song = 5 * getDownload();
    }

private:
int song;

};

class Nosebook:public App{
public: 
	// default constructor is necessary
	Nosebook(int d = 0):App(d){
        Friend = 3 * getDownload() + 5;
    }
    
    int getFriend(){
        return Friend;
    }

    void update(){
        Friend = 3 * getDownload() + 5;
    }
    
private:
int Friend;
   
};

void main_block(){
    int JB_volume , NB_friend;
    cin >> JB_volume >> NB_friend;
    JJBox jjbox(JB_volume);
    Nosebook nosebook(NB_friend);
    int action;
    while(1){
        cin >> action;
        switch(action){
            case 1:
            jjbox.increaseDownload();
            break;
        
            case 2:
            nosebook.increaseDownload();
            break;

            case 3:
            jjbox.increaseDownload();
            nosebook.increaseDownload();
            break;
            
            case 4:
            jjbox.update();
            break;
            
            case 5:
            nosebook.update();
            break;   
        
        }
        if(action == -1) {return;}
        cout << "JJBox now has " <<jjbox.getsongs() << " songs." << "\n";
        cout << "NoseBook now has " << nosebook.getFriend() << " friends." << "\n";
        cout << "==========" << "\n";
        
    }
    return;
}