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

# Challenge Notebook¶

## Constraints¶

• Is the input an array of ints?
• Yes
• Is the output a new array of ints?
• No, do this in-place
• Do we need to maintain ordering of non-zero values?
• Yes
• Can we assume the inputs are valid?
• No
• Can we assume this fits memory?
• Yes

## Test Cases¶

* None -> TypeError
* [0, 1, 0, 3, 12]
* [1, 0] -> [1, 0]
* [0, 1] -> [1, 0]
* [0] -> [0]
* [1] -> [1]
* [1, 1] -> [1, 1]


## 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 Solution(object):

def move_zeroes(self, nums):
# TODO: Implement me
pass


## Unit Test¶

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

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

class TestMoveZeroes(unittest.TestCase):

def test_move_zeroes(self):
solution = Solution()
self.assertRaises(TypeError, solution.move_zeroes, None)
array = [0, 1, 0, 3, 12]
solution.move_zeroes(array)
self.assertEqual(array, [1, 3, 12, 0, 0])
array = [1, 0]
solution.move_zeroes(array)
self.assertEqual(array, [1, 0])
array = [0, 1]
solution.move_zeroes(array)
self.assertEqual(array, [1, 0])
array = [0]
solution.move_zeroes(array)
self.assertEqual(array, [0])
array = [1]
solution.move_zeroes(array)
self.assertEqual(array, [1])
array = [1, 1]
solution.move_zeroes(array)
self.assertEqual(array, [1, 1])
print('Success: test_move_zeroes')

def main():
test = TestMoveZeroes()
test.test_move_zeroes()

if __name__ == '__main__':
main()


## Solution Notebook¶

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