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

# Challenge Notebook¶

## Constraints¶

• Is a naive solution sufficient (ie not stable, not based on a heap)?
• Yes
• Are duplicates allowed?
• Yes
• Can we assume the input is valid?
• No
• Can we assume this fits memory?
• Yes

## Test Cases¶

• None -> Exception
• Empty input -> []
• One element -> [element]
• Two or more elements

## 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 SelectionSort(object):

def sort(self, data):
# TODO: Implement me (recursive)
pass


## Unit Test¶

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

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

class TestSelectionSort(unittest.TestCase):

def test_selection_sort(self, func):
print('None input')
self.assertRaises(TypeError, func, None)

print('Empty input')
self.assertEqual(func([]), [])

print('One element')
self.assertEqual(func([5]), [5])

print('Two or more elements')
data = [5, 1, 7, 2, 6, -3, 5, 7, -10]
self.assertEqual(func(data), sorted(data))

print('Success: test_selection_sort\n')

def main():
test = TestSelectionSort()
selection_sort = SelectionSort()
test.test_selection_sort(selection_sort.sort)
try:
test.test_selection_sort(selection_sort.sort_recursive)
test.test_selection_sort(selection_sort.sor_iterative_alt)
except NameError:
# Alternate solutions are only defined
# in the solutions file
pass

if __name__ == '__main__':
main()


## Solution Notebook¶

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