A client wants to launch an e-commerce site to promote their brand, below are some of the products that they will be listing:

Products

ID	Name	Price
0001	Water Bottle	24.95
0002	Hoodie	65.00
0003	Sticker Set	3.99

The marketing team would like to run the following promotions;

• If you spend over £75 then you get a 10% discount
• If you buy two or more water bottles then the price drops to £22.99 each

Multiple promotions can be applied to the same checkout

The checkout system needs to be able to scan the items in any order then apply the promotion rules. These rules should be allowed to change over time. The pseudocode below outlines the interface for the checkout

checkout = new checkout(promotionalRules) checkout.scan(items) //List of item objects created from the products above println(checkout.total()) //e.g. £68.99

Implement a checkout that meets these requirements. Do not worry about the storage or retrieval of any items in a database, for the purpose of this test they only need to be processed.

Test Data

• Items: 0001,0001,0002,0003 - Total Price: £114.97
• Items: 0001,0001,0001 - Total Price: £68.97
• Items: 0002,0002,0003 - Total Price: £120.59