HarryPotter kata for practice TDD implemented in Java by Jorge Sánchez (Xurxodev)
To try and encourage more sales of the 5 different Harry Potter books they sell, a bookshop has decided to offer discounts of multiple-book purchases.
One copy of any of the five books costs 8 EUR.
If, however, you buy two different books, you get a 5% discount on those two books.
If you buy 3 different books, you get a 10% discount.
If you buy 4 different books, you get a 20% discount.
If you go the whole hog, and buy all 5, you get a huge 25% discount.
Note that if you buy, say, four books, of which 3 are different titles, you get a 10% discount on the 3 that form part of a set, but the fourth book still costs 8 EUR.
Your mission is to write a piece of code to calculate the price of any conceivable shopping basket (containing only Harry Potter books), giving as big a discount as possible.
For example, how much does this basket of books cost?
- 2 copies of the first book
- 2 copies of the second book
- 2 copies of the third book
- 1 copy of the fourth book
- 1 copy of the fifth book
Answer: 51.20 EUR
|1||1 * 8||8.00|
|1||1||2 * 8 * 0.95||15.20|
|1||1||1||3 * 8 * 0.9||21.60|
|1||1||1||1||4 * 8 * 0.8||25.60|
|1||1||1||1||1||5 * 8 * 0.75||30.00|
|2||2 * 8||16.00|
|2||1||2 * 8 * 0.95 + 1 * 8||23.20|
|2||1||1||3 * 8 * 0.90 + 1 * 8||29.60|
|2||2||2||1||1||4 * 8 * 0.8 + 4 * 8 * 0.8||51.20|
- Jorge Sánchez Fernández aka xurxodev
Copyright 2016 Jorge Sánchez Fernández Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.