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

# Challenge Notebook¶

## Constraints¶

• Does A have enough space for B?
• Yes
• Can the inputs have duplicate array items?
• Yes
• Can we assume the inputs are valid?
• No
• Does the inputs also include the actual size of A and B?
• Yes
• Can we assume this fits memory?
• Yes

## Test Cases¶

• A or B is None -> Exception
• index of last A or B < 0 -> Exception
• A or B is empty
• General case
• A = [1, 3, 5, 7, 9, None, None, None]
• B = [4, 5, 6]
• A = [1, 3, 4, 5, 5, 6, 7, 9]

## 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 Array(object):

def merge_into(self, source, dest, source_end_index, dest_end_index):
# TODO: Implement me
pass


## Unit Test¶

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

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

class TestArray(unittest.TestCase):

def test_merge_into(self):
array = Array()
self.assertRaises(TypeError, array.merge_into, None, None, None, None)
self.assertRaises(ValueError, array.merge_into, [1], [2], -1, -1)
a = [1, 2, 3]
self.assertEqual(array.merge_into(a, [], len(a), 0), [1, 2, 3])
a = [1, 2, 3]
self.assertEqual(array.merge_into(a, [], len(a), 0), [1, 2, 3])
a = [1,  3,  5,  7,  9,  None,  None,  None]
b = [4,  5,  6]
expected = [1, 3, 4, 5, 5, 6, 7, 9]
self.assertEqual(array.merge_into(a, b, 5, len(b)), expected)
print('Success: test_merge_into')

def main():
test = TestArray()
test.test_merge_into()

if __name__ == '__main__':
main()


## Solution Notebook¶

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