Money

//Money.h

#ifndef _MONEY_H_
#define _MONEY_H_

typedef double lf;

class Money
{
 public:
    virtual ~Money()                   = 0;
    virtual lf get_money()             = 0;
    virtual void set_money(lf)         = 0;
    virtual lf del()                   = 0;
    void add(Money*);
};

class Ruble : public Money
{
 public:
    ~Ruble()                   override;
    lf get_money()             override;
    void set_money(lf)         override;
    lf del()                   override;


 private:
    lf currency = 1;
    lf collect;
};

class Dollar : public Money
{
 public:
    ~Dollar()                  override;
    lf get_money()             override;
    void set_money(lf)         override;
    lf del()                   override;


 private:
    lf currency = 69.29;
    lf collect;
};

class Euro : public Money
{
 public:
    ~Euro()                    override;
    lf get_money()             override;
    void set_money(lf)         override;
    lf del()                   override;


 private:
    lf currency = 77.84;
    lf collect;
};

#endif//_MONEY_H_



//Money.cpp

#include "Money.h"

lf Ruble::get_money()
{
    const lf get = collect;
    return get;
}

void Ruble::set_money( const lf set )
{
    collect = set;
}

lf Ruble::del()
{
    return currency;
}

Ruble::~Ruble() = default;



lf Dollar::get_money()
{
    const lf get = collect;
    return get;
}

void Dollar::set_money( const lf set )
{
    collect = set;
}

lf Dollar::del()
{
    return currency;
}

Dollar::~Dollar() = default;



lf Euro::get_money()
{
    const lf get = collect;
    return get;
}

void Euro::set_money( const lf set )
{
    collect = set;
}

lf Euro::del()
{
    return currency;
}

Euro::~Euro() = default;



Money::~Money() = default;

void Money::add(Money* a)
{
    set_money(a -> get_money() * a -> del() / del() + get_money());
}




//main.cpp

#include "Money.h"
#include <cstdio>

int main()
{
    Ruble r;
    Dollar d;
    Euro e;
    lf rub = 0, dol = 0, ero = 0;
    int choice = 0;
    std::printf("The amount of rubles: ");
    std::scanf("%lf", &rub);
    r.set_money(rub);
    std::printf("The amount of dollars: ");
    std::scanf("%lf", &dol);
    d.set_money(dol);
    std::printf("The amount of euro: ");
    std::scanf("%lf", &ero);
    e.set_money(ero);
    do
    {
        std::printf("Transfer to a single currency Select 1) RUBLE 2) DOLLAR 3) EURO: ");
        std::scanf("%d", &choice);
        if(choice > 3) std::printf("Incorrect input\n");
    }
    while(choice > 3);
    switch (choice)
    {
    case 1:
        r.add(&d);
        r.add(&e);
        std::printf("%lf rubles", r.get_money());
        break;
    case 2:
        d.add(&r);
        d.add(&e);
        std::printf("%lf dollars", d.get_money());
        break;
    default:
        e.add(&r);
        e.add(&d);
        std::printf("%lf euros", e.get_money());
        break;
    }
    return 0;
}