This notebook was prepared by Donne Martin. Source and license info is on GitHub.

# Challenge Notebook¶

## Constraints¶

• Should the resulting subsets be unique?
• Yes, treat 'ab' and 'bc' as the same
• Is the empty set included as a subset?
• Yes
• Are the inputs unique?
• No
• Can we assume the inputs are valid?
• No
• Can we assume this fits memory?
• Yes

## Test Cases¶

* None -> None
* [] -> [[]]
* ['a'] -> [[],
['a']]
* ['a', 'b'] -> [[],
['a'],
['b'],
['a', 'b']]
* ['a', 'b', 'c'] -> [[],
['a'],
['b'],
['c'],
['a', 'b'],
['a', 'c'],
['b', 'c'],
['a', 'b', 'c']]


## Algorithm¶

Refer to the Solution Notebook. If you are stuck and need a hint, the solution notebook's algorithm discussion might be a good place to start.

## Code¶

In [ ]:
class Sets(object):

def find_power_set_recursive(self, input_set):
# TODO: Implement me
pass

def find_power_set_iterative(self, input_set):
# TODO: Implement me
pass


## Unit Test¶

The following unit test is expected to fail until you solve the challenge.

In [ ]:
# %load test_power_set.py
import unittest

class TestPowerSet(unittest.TestCase):

def test_power_set(self):
input_set = []
expected = [[]]
self.run_test(input_set, expected)
input_set = ['a']
expected = [['a'], []]
self.run_test(input_set, expected)
input_set = ['a', 'b']
expected = [['a'], ['a', 'b'], ['b'], []]
self.run_test(input_set, expected)
input_set = ['a', 'b', 'c']
expected = [['a'], ['a', 'b'], ['b'], ['a', 'c'],
['a', 'b', 'c'], ['b', 'c'], ['c'], []]
self.run_test(input_set, expected)
print('Success: test_power_set')

def run_test(self, input_set, expected):
combinatoric = Combinatoric()
result = combinatoric.find_power_set_recursive(input_set)
self.assertEqual(result, expected)
result = combinatoric.find_power_set_iterative(input_set)
self.assertEqual(result, expected)

def main():
test = TestPowerSet()
test.test_power_set()

if __name__ == '__main__':
main()


## Solution Notebook¶

Review the Solution Notebook for a discussion on algorithms and code solutions.