[Applied] Build a Mini Inventory Management System

This lesson combines the classes, vectors, and structs you've learned so far to build a simple inventory management system — the capstone of this C++ introduction.

In a real business system, a common combination is representing data like a "product" as a class or struct, then managing a collection of products together in a vector.

The example represents a product (name and quantity) with class Item, manages a list of products using a vector inside class Inventory, and prints a status message for each one.

The pointers, references, classes, and vectors covered across these lessons are foundational ideas in real business-system and game-development design too. Building the habit of writing even small programs while staying conscious of how memory works is the shortcut to using C++ professionally.

📖 Reference code

#include <iostream>
#include <vector>
#include <string>

class Item {
public:
    std::string name;
    int quantity;
    Item(std::string n, int q) : name(n), quantity(q) {}
};

class Inventory {
private:
    std::vector<Item> items;
public:
    void add(const Item& item) {
        items.push_back(item);
    }
    void report() {
        for (auto& item : items) {
            std::string status;
            if (item.quantity == 0) status = "Out of stock";
            else if (item.quantity < 5) status = "Low stock";
            else status = "In stock";
            std::cout << item.name << ": " << item.quantity << " (" << status << ")" << std::endl;
        }
    }
};

int main() {
    Inventory inv;
    inv.add(Item("Notebook", 12));
    inv.add(Item("Eraser", 3));
    inv.add(Item("Ruler", 0));
    inv.report();
    return 0;
}

✍️ Your code

Type your code, then press "Run"

🧪 This site can't compile or run C++ directly, so it checks on the spot whether what you typed matches the reference code (scoring happens entirely in your browser — nothing is sent anywhere).