From f2aa27e9158500823f61ecff0c1f2046c0227d6a Mon Sep 17 00:00:00 2001 From: Xevion Date: Wed, 17 Jul 2019 02:51:33 -0500 Subject: [PATCH] rot cipher, difference of squares exercises --- .../.exercism/metadata.json | 1 + python/difference-of-squares/README.md | 62 ++++++++++++++ .../difference_of_squares.py | 10 +++ .../difference_of_squares_test.py | 42 ++++++++++ .../rotational-cipher/.exercism/metadata.json | 1 + python/rotational-cipher/README.md | 80 +++++++++++++++++++ python/rotational-cipher/rotational_cipher.py | 5 ++ .../rotational_cipher_test.py | 48 +++++++++++ 8 files changed, 249 insertions(+) create mode 100644 python/difference-of-squares/.exercism/metadata.json create mode 100644 python/difference-of-squares/README.md create mode 100644 python/difference-of-squares/difference_of_squares.py create mode 100644 python/difference-of-squares/difference_of_squares_test.py create mode 100644 python/rotational-cipher/.exercism/metadata.json create mode 100644 python/rotational-cipher/README.md create mode 100644 python/rotational-cipher/rotational_cipher.py create mode 100644 python/rotational-cipher/rotational_cipher_test.py diff --git a/python/difference-of-squares/.exercism/metadata.json b/python/difference-of-squares/.exercism/metadata.json new file mode 100644 index 0000000..7a42ce5 --- /dev/null +++ b/python/difference-of-squares/.exercism/metadata.json @@ -0,0 +1 @@ +{"track":"python","exercise":"difference-of-squares","id":"79021d92f5b24650af12a464a9f6e9d6","url":"https://exercism.io/my/solutions/79021d92f5b24650af12a464a9f6e9d6","handle":"Xevion","is_requester":true,"auto_approve":false} \ No newline at end of file diff --git a/python/difference-of-squares/README.md b/python/difference-of-squares/README.md new file mode 100644 index 0000000..8b4c0de --- /dev/null +++ b/python/difference-of-squares/README.md @@ -0,0 +1,62 @@ +# Difference Of Squares + +Find the difference between the square of the sum and the sum of the squares of the first N natural numbers. + +The square of the sum of the first ten natural numbers is +(1 + 2 + ... + 10)² = 55² = 3025. + +The sum of the squares of the first ten natural numbers is +1² + 2² + ... + 10² = 385. + +Hence the difference between the square of the sum of the first +ten natural numbers and the sum of the squares of the first ten +natural numbers is 3025 - 385 = 2640. + +## 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 the appropriate command below ([why they are different](https://github.com/pytest-dev/pytest/issues/1629#issue-161422224)): + +- Python 2.7: `py.test difference_of_squares_test.py` +- Python 3.4+: `pytest difference_of_squares_test.py` + +Alternatively, you can tell Python to run the pytest module (allowing the same command to be used regardless of Python version): +`python -m pytest difference_of_squares_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/difference-of-squares` 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 + +Problem 6 at Project Euler [http://projecteuler.net/problem=6](http://projecteuler.net/problem=6) + +## Submitting Incomplete Solutions + +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/python/difference-of-squares/difference_of_squares.py b/python/difference-of-squares/difference_of_squares.py new file mode 100644 index 0000000..8bf0c35 --- /dev/null +++ b/python/difference-of-squares/difference_of_squares.py @@ -0,0 +1,10 @@ +def square_of_sum(number): + return sum(range(1, number + 1)) ** 2 + + +def sum_of_squares(number): + return sum(i ** 2 for i in range(1, number + 1)) + + +def difference_of_squares(number): + return abs(square_of_sum(number) - sum_of_squares(number)) \ No newline at end of file diff --git a/python/difference-of-squares/difference_of_squares_test.py b/python/difference-of-squares/difference_of_squares_test.py new file mode 100644 index 0000000..1020f8d --- /dev/null +++ b/python/difference-of-squares/difference_of_squares_test.py @@ -0,0 +1,42 @@ +import unittest + +from difference_of_squares import ( + difference_of_squares, + square_of_sum, + sum_of_squares +) + + +# Tests adapted from `problem-specifications//canonical-data.json` @ v1.2.0 + +class DifferenceOfSquaresTest(unittest.TestCase): + def test_square_of_sum_1(self): + self.assertEqual(square_of_sum(1), 1) + + def test_square_of_sum_5(self): + self.assertEqual(square_of_sum(5), 225) + + def test_square_of_sum_100(self): + self.assertEqual(square_of_sum(100), 25502500) + + def test_sum_of_squares_1(self): + self.assertEqual(sum_of_squares(1), 1) + + def test_sum_of_squares_5(self): + self.assertEqual(sum_of_squares(5), 55) + + def test_sum_of_squares_100(self): + self.assertEqual(sum_of_squares(100), 338350) + + def test_difference_of_squares_1(self): + self.assertEqual(difference_of_squares(1), 0) + + def test_difference_of_squares_5(self): + self.assertEqual(difference_of_squares(5), 170) + + def test_difference_of_squares_100(self): + self.assertEqual(difference_of_squares(100), 25164150) + + +if __name__ == '__main__': + unittest.main() diff --git a/python/rotational-cipher/.exercism/metadata.json b/python/rotational-cipher/.exercism/metadata.json new file mode 100644 index 0000000..bebd1a9 --- /dev/null +++ b/python/rotational-cipher/.exercism/metadata.json @@ -0,0 +1 @@ +{"track":"python","exercise":"rotational-cipher","id":"83ee13c77e1d4de898c100f544771cf7","url":"https://exercism.io/my/solutions/83ee13c77e1d4de898c100f544771cf7","handle":"Xevion","is_requester":true,"auto_approve":false} \ No newline at end of file diff --git a/python/rotational-cipher/README.md b/python/rotational-cipher/README.md new file mode 100644 index 0000000..4b8a3cf --- /dev/null +++ b/python/rotational-cipher/README.md @@ -0,0 +1,80 @@ +# Rotational Cipher + +Create an implementation of the rotational cipher, also sometimes called the Caesar cipher. + +The Caesar cipher is a simple shift cipher that relies on +transposing all the letters in the alphabet using an integer key +between `0` and `26`. Using a key of `0` or `26` will always yield +the same output due to modular arithmetic. The letter is shifted +for as many values as the value of the key. + +The general notation for rotational ciphers is `ROT + `. +The most commonly used rotational cipher is `ROT13`. + +A `ROT13` on the Latin alphabet would be as follows: + +```text +Plain: abcdefghijklmnopqrstuvwxyz +Cipher: nopqrstuvwxyzabcdefghijklm +``` + +It is stronger than the Atbash cipher because it has 27 possible keys, and 25 usable keys. + +Ciphertext is written out in the same formatting as the input including spaces and punctuation. + +## Examples + +- ROT5 `omg` gives `trl` +- ROT0 `c` gives `c` +- ROT26 `Cool` gives `Cool` +- ROT13 `The quick brown fox jumps over the lazy dog.` gives `Gur dhvpx oebja sbk whzcf bire gur ynml qbt.` +- ROT13 `Gur dhvpx oebja sbk whzcf bire gur ynml qbt.` gives `The quick brown fox jumps over the lazy dog.` + +## 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 the appropriate command below ([why they are different](https://github.com/pytest-dev/pytest/issues/1629#issue-161422224)): + +- Python 2.7: `py.test rotational_cipher_test.py` +- Python 3.4+: `pytest rotational_cipher_test.py` + +Alternatively, you can tell Python to run the pytest module (allowing the same command to be used regardless of Python version): +`python -m pytest rotational_cipher_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/rotational-cipher` 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 + +Wikipedia [https://en.wikipedia.org/wiki/Caesar_cipher](https://en.wikipedia.org/wiki/Caesar_cipher) + +## Submitting Incomplete Solutions + +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/python/rotational-cipher/rotational_cipher.py b/python/rotational-cipher/rotational_cipher.py new file mode 100644 index 0000000..47051d2 --- /dev/null +++ b/python/rotational-cipher/rotational_cipher.py @@ -0,0 +1,5 @@ +from string import ascii_letters + +def rotate(text, key): + key = key % 26 + return text.translate(str.maketrans(ascii_letters, ascii_letters[key:26] + ascii_letters[:key] + ascii_letters[26+key:] + ascii_letters[26:26 + key])) \ No newline at end of file diff --git a/python/rotational-cipher/rotational_cipher_test.py b/python/rotational-cipher/rotational_cipher_test.py new file mode 100644 index 0000000..925c528 --- /dev/null +++ b/python/rotational-cipher/rotational_cipher_test.py @@ -0,0 +1,48 @@ +import unittest + +import rotational_cipher + + +# Tests adapted from `problem-specifications//canonical-data.json` @ v1.2.0 + +class RotationalCipherTest(unittest.TestCase): + def test_rotate_a_by_0(self): + self.assertEqual(rotational_cipher.rotate('a', 0), 'a') + + def test_rotate_a_by_1(self): + self.assertEqual(rotational_cipher.rotate('a', 1), 'b') + + def test_rotate_a_by_26(self): + self.assertEqual(rotational_cipher.rotate('a', 26), 'a') + + def test_rotate_m_by_13(self): + self.assertEqual(rotational_cipher.rotate('m', 13), 'z') + + def test_rotate_n_by_13_with_wrap_around_alphabet(self): + self.assertEqual(rotational_cipher.rotate('n', 13), 'a') + + def test_rotate_capital_letters(self): + self.assertEqual(rotational_cipher.rotate('OMG', 5), 'TRL') + + def test_rotate_spaces(self): + self.assertEqual(rotational_cipher.rotate('O M G', 5), 'T R L') + + def test_rotate_numbers(self): + self.assertEqual( + rotational_cipher.rotate('Testing 1 2 3 testing', 4), + 'Xiwxmrk 1 2 3 xiwxmrk') + + def test_rotate_punctuation(self): + self.assertEqual( + rotational_cipher.rotate("Let's eat, Grandma!", 21), + "Gzo'n zvo, Bmviyhv!") + + def test_rotate_all_letters(self): + self.assertEqual( + rotational_cipher.rotate("The quick brown fox jumps" + " over the lazy dog.", 13), + "Gur dhvpx oebja sbk whzcf bire gur ynml qbt.") + + +if __name__ == '__main__': + unittest.main()