A shop inventory manager

The problem

Build a program that tracks a shop's products, stock levels and sales, and produces reports.

Requirements

• A Money class stores amounts in whole paisa and supports +, -, * by a count, comparison and printing
• A Product class keeps a name, a price and a stock level, and refuses to sell more than it has
• Products are stored in a map from product code, and can be listed in order of code, price or stock
• Selling, restocking and removing products report problems with exceptions
• A report shows the total value of the stock and the products that are running low
• A class template is used for at least one reusable piece, such as a sorted report

Technologies

• C++
• Classes
• Operator overloading
• Templates
• map and vector
• sort

Step by step

1. Write and test the Money class with its operators.
2. Write Product with checked member functions for selling and restocking.
3. Store products in a map, and add commands to add, sell, restock and remove them.
4. Write the reports, sorting copies of the products with comparison functions.
5. Write a small class template, such as a top-N list, and use it in a report.
6. Report every bad command with an exception, caught in the command loop.
7. Test selling out, unknown codes, and a report with no products.

Expected result

A working inventory manager that keeps exact amounts of money and never sells stock it does not have.

How it is evaluated

• Money is exact: no floating-point rounding errors appear in any total
• Stock can never become negative
• Reports are correct and sorted as asked
• Classes are small, const-correct and easy to read

Ways to improve it

• Record every sale with a date and show daily totals
• Add product categories with their own discount rules
• Load the starting stock from a file