Here is a simple implementation in C++: ```cpp #include using namespace std; class Item { protected: string itemID; int daysOverdue; public: Item(string id, int days) : itemID(id), daysOverdue(days) {} virtual double calculateLateFees() = 0; // Pure virtual function }; class Book : public Item { public: Book(string id, int days) : Item(id, days) {} double calculateLateFees() { return daysOverdue * 0.25; } }; class DVD : public Item { public: DVD(string id, int days) : Item(id, days) {} double calculateLateFees() { return daysOverdue * 0.50; } }; class Magazine : public Item { public: Magazine(string id, int days) : Item(id, days) {} double calculateLateFees() { return daysOverdue * 0.10; } }; int main() { Book b("B1", 5); DVD d("D1", 3); Magazine m("M1", 7); double totalOverdue = b.calculateLateFees() + d.calculateLateFees() + m.calculateLateFees(); cout

Question

Here is a simple implementation in C++:

```cpp
#include<iostream>
using namespace std;

class Item {
protected:
    string itemID;
    int daysOverdue;
public:
    Item(string id, int days) : itemID(id), daysOverdue(days) {}
    virtual double calculateLateFees() = 0; // Pure virtual function
};

class Book : public Item {
public:
    Book(string id, int days) : Item(id, days) {}
    double calculateLateFees() {
        return daysOverdue * 0.25;
    }
};

class DVD : public Item {
public:
    DVD(string id, int days) : Item(id, days) {}
    double calculateLateFees() {
        return daysOverdue * 0.50;
    }
};

class Magazine : public Item {
public:
    Magazine(string id, int days) : Item(id, days) {}
    double calculateLateFees() {
        return daysOverdue * 0.10;
    }
};

int main() {
    Book b("B1", 5);
    DVD d("D1", 3);
    Magazine m("M1", 7);

double totalOverdue = b.calculateLateFees() + d.calculateLateFees() + m.calculateLateFees();

cout << "Total overdue amount: Rs. " << totalOverdue << endl;

return 0;
}
```

In this code, we have a base class `Item` with two data members `itemID` and `daysOverdue`. The `calculateLateFees` function is a pure virtual function, meaning it must be implemented in any derived classes.

We then have three derived classes `Book`, `DVD`, and `Magazine`, each implementing the `calculateLateFees` function according to their respective rates.

In the `main` function, we create one instance of each item type, calculate their late fees, and add them up to get the total overdue amount.

Knowee AI · Accepted Answer