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

# Challenge Notebook¶

## Constraints¶

• Can we assume we already have a stack class that can be used for this problem?
• Yes
• Are all stack bound by the same capacity?
• Yes
• If a stack becomes full, should automatically create one?
• Yes
• If a stack becomes empty, should we delete it?
• Yes
• If we pop on an empty stack, should we return None?
• Yes
• Can we assume this fits memory?
• Yes

## Test Cases¶

• Push and pop on an empty stack
• Push and pop on a non-empty stack
• Push on a capacity stack to create a new one
• Pop on a stack to destroy it

## 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 [ ]:
%run ../stack/stack.py

In [ ]:
class StackWithCapacity(Stack):

def __init__(self, top=None, capacity=10):
# TODO: Implement me
pass

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

def pop(self):
# TODO: Implement me
pass

def is_full(self):
# TODO: Implement me
pass

class SetOfStacks(object):

def __init__(self, indiv_stack_capacity):
# TODO: Implement me
pass

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

def pop(self):
# TODO: Implement me
pass


## Unit Test¶

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

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

class TestSetOfStacks(unittest.TestCase):

def test_set_of_stacks(self):
print('Test: Push on an empty stack')
stacks = SetOfStacks(indiv_stack_capacity=2)
stacks.push(3)

print('Test: Push on a non-empty stack')
stacks.push(5)

print('Test: Push on a capacity stack to create a new one')
stacks.push('a')

print('Test: Pop on a stack to destroy it')
self.assertEqual(stacks.pop(), 'a')

print('Test: Pop general case')
self.assertEqual(stacks.pop(), 5)
self.assertEqual(stacks.pop(), 3)

print('Test: Pop on no elements')
self.assertEqual(stacks.pop(), None)

print('Success: test_set_of_stacks')

def main():
test = TestSetOfStacks()
test.test_set_of_stacks()

if __name__ == '__main__':
main()


## Solution Notebook¶

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