checkout.md

Checkout

Model and implement the checkout from a super market:

Step 1

• Calculate the overall sum for a checkout
• You'll receive a list of prices

Step 2

• An item is identified by a single letter (e.g. "A", "B", …)
• Each item has a defined price, e.g.
  • A = 30
  • B = 10
• The order is represented as a string of item identifiers (e.g. "ABBC")
  • Items may occur in arbitrary order

Step 3

• You should also be able to scan several order strings in a row to combine them
  • e.g. "ABB", then "CB" and the resulting order is "ABBBC"

Step 4

• There are additional rules that define extraordinary prices, e.g.
  • "Buy two A for 45"
  • "Buy three A and get one for free"

Step 5

• Rules may change over time
  • e.g. every week