Here comes my solution for TrackTik PHP Backend challange. I have separated the main classes to make it easier to view them on screen.

1. This code in compatible with PHP 7.2+
2. The main file is index.php

I tried to apply the PSR-2 conceptions along with part of SOLID elements.

1. There must be an extras number validation
2. Controllers can have their own price
3. Controller price is added to product price in "total price calculation"

1. Sorting by price function returns bool value intead of the list
2. Sorting by price function merges items with the same price

• Price 500
• Wired controllers 2x 25
• Remote controllers 2x 60
• Total Price 670

• Price 900
• Remote controllers 2x20
• Total Price 940

• Price 400
• Remote controllers 20
• Total Price 420

• Price 90
• Total Price 90

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