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

# Challenge Notebook¶

## Constraints¶

• Is the input number an int?
• Yes
• Can we assume the inputs are valid?
• No
• Is the output a boolean?
• Yes
• Can we assume this fits memory?
• Yes

## Test Cases¶

• None -> TypeError
• 0 -> False
• 1 -> True
• 2 -> True
• 15 -> False
• 16 -> True

## 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 is_power_of_two(self, val):
# TODO: Implement me
pass


## Unit Test¶

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

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

class TestSolution(unittest.TestCase):

def test_is_power_of_two(self):
solution = Solution()
self.assertRaises(TypeError, solution.is_power_of_two, None)
self.assertEqual(solution.is_power_of_two(0), False)
self.assertEqual(solution.is_power_of_two(1), True)
self.assertEqual(solution.is_power_of_two(2), True)
self.assertEqual(solution.is_power_of_two(15), False)
self.assertEqual(solution.is_power_of_two(16), True)
print('Success: test_is_power_of_two')

def main():
test = TestSolution()
test.test_is_power_of_two()

if __name__ == '__main__':
main()


## Solution Notebook¶

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