Finished working on the book-store challenge, started working on the leap challenge

Author: sinanata

book-store/__pycache__/book_store.cpython-37.pyc

@@ -1,55 +1,30 @@
-"""
-One copy of any of the five books costs $8.
+from collections import Counter
 
-If, however, you buy two different books, you get a 5% discount on those two books.
+PRICE = 800
 
-If you buy 3 different books, you get a 10% discount.
+PRICE_PER_GROUP = {
+    1: 1 * PRICE * 1.00,
+    2: 2 * PRICE * 0.95,
+    3: 3 * PRICE * 0.90,
+    4: 4 * PRICE * 0.80,
+    5: 5 * PRICE * 0.75,
+}
 
-If you buy 4 different books, you get a 20% discount.
-
-If you buy all 5, you get a 25% discount.
-
-Note: that if you buy 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.
-
-Your mission is to write a piece of code to calculate the price of any conceivable shopping basket (containing only books of the same series), 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
-One way of grouping these 8 books is:
-
-1 group of 5 --> 25% discount (1st,2nd,3rd,4th,5th)
-+1 group of 3 --> 10% discount (1st,2nd,3rd)
-This would give a total of:
-
-5 books at a 25% discount
-+3 books at a 10% discount
-Resulting in:
-
-5 x (8 - 2.00) == 5 x 6.00 == $30.00
-+3 x (8 - 0.80) == 3 x 7.20 == $21.60
-For a total of $51.60
-
-However, a different way to group these 8 books is:
-
-1 group of 4 books --> 20% discount (1st,2nd,3rd,4th)
-+1 group of 4 books --> 20% discount (1st,2nd,3rd,5th)
-This would give a total of:
+def total(basket):
+    if not basket:
+        return 0
 
-4 books at a 20% discount
-+4 books at a 20% discount
-Resulting in:
+    books_collection = Counter(basket)
+    prices = [PRICE * len(basket)]
 
-4 x (8 - 1.60) == 4 x 6.40 == $25.60
-+4 x (8 - 1.60) == 4 x 6.40 == $25.60
-For a total of $51.20
+    for max_group_size in range(2, len(books_collection) + 1):
+        remaining_books_in_collection = books_collection.copy()
+        prices.append(0)
+        while remaining_books_in_collection:
+            books_group_collection = Counter(b[0] for b in remaining_books_in_collection.most_common(max_group_size))
+            prices[max_group_size - 1] += PRICE_PER_GROUP[len(books_group_collection)]
+            remaining_books_in_collection -= books_group_collection
 
-And $51.20 is the price with the biggest discount.
-"""
+    return min(prices)
 
-def total(basket):
     pass

book-store/__pycache__/book_store_test.cpython-37-pytest-5.2.2.pyc

@@ -0,0 +1 @@
+{"track":"python","exercise":"leap","id":"f1fd3d7f2d1648759a688764ca7acecb","url":"https://exercism.io/my/solutions/f1fd3d7f2d1648759a688764ca7acecb","handle":"sinanata","is_requester":true,"auto_approve":false}

book-store/book_store.py

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+# Leap
+
+Given a year, report if it is a leap year.
+
+The tricky thing here is that a leap year in the Gregorian calendar occurs:
+
+```text
+on every year that is evenly divisible by 4
+  except every year that is evenly divisible by 100
+    unless the year is also evenly divisible by 400
+```
+
+For example, 1997 is not a leap year, but 1996 is.  1900 is not a leap
+year, but 2000 is.
+
+## Notes
+
+Though our exercise adopts some very simple rules, there is more to
+learn!
+
+For a delightful, four minute explanation of the whole leap year
+phenomenon, go watch [this youtube video][video].
+
+[video]: http://www.youtube.com/watch?v=xX96xng7sAE
+
+
+## Exception messages
+
+Sometimes it is necessary to raise an exception. When you do this, you should include a meaningful error message to
+indicate what the source of the error is. This makes your code more readable and helps significantly with debugging. Not
+every exercise will require you to raise an exception, but for those that do, the tests will only pass if you include
+a message.
+
+To raise a message with an exception, just write it as an argument to the exception type. For example, instead of
+`raise Exception`, you should write:
+
+```python
+raise Exception("Meaningful message indicating the source of the error")
+```
+
+## Running the tests
+
+To run the tests, run `pytest leap_test.py`
+
+Alternatively, you can tell Python to run the pytest module:
+`python -m pytest leap_test.py`
+
+### Common `pytest` options
+
+- `-v` : enable verbose output
+- `-x` : stop running tests on first failure
+- `--ff` : run failures from previous test before running other test cases
+
+For other options, see `python -m pytest -h`
+
+## Submitting Exercises
+
+Note that, when trying to submit an exercise, make sure the solution is in the `$EXERCISM_WORKSPACE/python/leap` directory.
+
+You can find your Exercism workspace by running `exercism debug` and looking for the line that starts with `Workspace`.
+
+For more detailed information about running tests, code style and linting,
+please see [Running the Tests](http://exercism.io/tracks/python/tests).
+
+## Source
+
+JavaRanch Cattle Drive, exercise 3 [http://www.javaranch.com/leap.jsp](http://www.javaranch.com/leap.jsp)
+
+## Submitting Incomplete Solutions
+
+It's possible to submit an incomplete solution so you can see how others have completed the exercise.

leap/.exercism/metadata.json

@@ -0,0 +1,2 @@
+def leap_year(year):
+    pass

leap/README.md

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+import unittest
+
+from leap import leap_year
+
+# Tests adapted from `problem-specifications//canonical-data.json` @ v1.6.0
+
+
+class LeapTest(unittest.TestCase):
+    def test_year_not_divisible_by_4_in_common_year(self):
+        self.assertIs(leap_year(2015), False)
+
+    def test_year_divisible_by_2_not_divisible_by_4_in_common_year(self):
+        self.assertIs(leap_year(1970), False)
+
+    def test_year_divisible_by_4_not_divisible_by_100_in_leap_year(self):
+        self.assertIs(leap_year(1996), True)
+
+    def test_year_divisible_by_4_and_5_is_still_a_leap_year(self):
+        self.assertIs(leap_year(1960), True)
+
+    def test_year_divisible_by_100_not_divisible_by_400_in_common_year(self):
+        self.assertIs(leap_year(2100), False)
+
+    def test_year_divisible_by_100_but_not_by_3_is_still_not_a_leap_year(self):
+        self.assertIs(leap_year(1900), False)
+
+    def test_year_divisible_by_400_in_leap_year(self):
+        self.assertIs(leap_year(2000), True)
+
+    def test_year_divisible_by_400_but_not_by_125_is_still_a_leap_year(self):
+        self.assertIs(leap_year(2400), True)
+
+    def test_year_divisible_by_200_not_divisible_by_400_in_common_year(self):
+        self.assertIs(leap_year(1800), False)
+
+
+if __name__ == "__main__":
+    unittest.main()