From 9d5ef578185dd45a1954f095658b67c3487a430e Mon Sep 17 00:00:00 2001 From: Donne Martin Date: Thu, 2 Jul 2015 23:05:48 -0400 Subject: [PATCH] Added set of stacks challenge. --- stacks_queues/set_of_stacks/__init__.py | 0 .../set_of_stacks_challenge.ipynb | 216 ++++++++++++++++++ .../set_of_stacks_solution.ipynb | 65 ++++-- .../set_of_stacks/test_set_of_stacks.py | 35 +++ 4 files changed, 300 insertions(+), 16 deletions(-) create mode 100644 stacks_queues/set_of_stacks/__init__.py create mode 100644 stacks_queues/set_of_stacks/set_of_stacks_challenge.ipynb create mode 100644 stacks_queues/set_of_stacks/test_set_of_stacks.py diff --git a/stacks_queues/set_of_stacks/__init__.py b/stacks_queues/set_of_stacks/__init__.py new file mode 100644 index 0000000..e69de29 diff --git a/stacks_queues/set_of_stacks/set_of_stacks_challenge.ipynb b/stacks_queues/set_of_stacks/set_of_stacks_challenge.ipynb new file mode 100644 index 0000000..5802d1b --- /dev/null +++ b/stacks_queues/set_of_stacks/set_of_stacks_challenge.ipynb @@ -0,0 +1,216 @@ +{ + "cells": [ + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "This notebook was prepared by [Donne Martin](http://donnemartin.com). Source and license info is on [GitHub](https://github.com/donnemartin/coding-challenges)." + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "# Challenge Notebook" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Problem: Implement SetOfStacks that wraps a list of stacks, where each stack is bound by a capacity.\n", + "\n", + "* [Constraints](#Constraints)\n", + "* [Test Cases](#Test-Cases)\n", + "* [Algorithm](#Algorithm)\n", + "* [Code](#Code)\n", + "* [Unit Test](#Unit-Test)\n", + "* [Solution Notebook](#Solution-Notebook)" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Constraints\n", + "\n", + "*Problem statements are sometimes ambiguous. Identifying constraints and stating assumptions can help to ensure you code the intended solution.*\n", + "\n", + "* Can we assume we already have a stack class that can be used for this problem?\n", + " * Yes\n", + "* If a stack becomes full, we should automatically create one?\n", + " * Yes\n", + "* If a stack becomes empty, should we delete it?\n", + " * Yes" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Test Cases\n", + "\n", + "* Push and pop on an empty stack\n", + "* Push and pop on a non-empty stack\n", + "* Push on a capacity stack to create a new one\n", + "* Pop on a one element stack to destroy it" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Algorithm\n", + "\n", + "Refer to the [Solution Notebook](http://nbviewer.ipython.org/github/donnemartin/coding-challenges/blob/master/stacks_queues/set_of_stacks/set_of_stacks_solution.ipynb). If you are stuck and need a hint, the solution notebook's algorithm discussion might be a good place to start." + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Code" + ] + }, + { + "cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": false + }, + "outputs": [], + "source": [ + "%run ../stack/stack.py\n", + "%load ../stack/stack.py" + ] + }, + { + "cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": false + }, + "outputs": [], + "source": [ + "class StackWithCapacity(Stack):\n", + " \n", + " def __init__(self, top=None, capacity=10):\n", + " # TODO: Implement me\n", + " pass\n", + "\n", + " def push(self, data):\n", + " # TODO: Implement me\n", + " pass\n", + "\n", + " def pop(self):\n", + " # TODO: Implement me\n", + " pass\n", + "\n", + " def is_full(self):\n", + " # TODO: Implement me\n", + " pass\n", + "\n", + "class SetOfStacks(object):\n", + " \n", + " def __init__(self, capacity):\n", + " # TODO: Implement me\n", + " pass\n", + "\n", + " def push(self, data):\n", + " # TODO: Implement me\n", + " pass\n", + "\n", + " def pop(self):\n", + " # TODO: Implement me\n", + " pass" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Unit Test\n", + "\n", + "\n", + "\n", + "**The following unit test is expected to fail until you solve the challenge.**" + ] + }, + { + "cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": false + }, + "outputs": [], + "source": [ + "# %load test_set_of_stacks.py\n", + "from nose.tools import assert_equal\n", + "\n", + "\n", + "class TestSetOfStacks(object):\n", + " \n", + " def test_set_of_stacks(self):\n", + " print('Test: Push on an empty stack')\n", + " capacity = 2\n", + " stacks = SetOfStacks(capacity)\n", + " stacks.push(3)\n", + "\n", + " print('Test: Push on a non-empty stack')\n", + " stacks.push(5)\n", + "\n", + " print('Test: Push on a capacity stack to create a new one')\n", + " stacks.push('a')\n", + "\n", + " print('Test: Pop on a one element stack to destroy it')\n", + " assert_equal(stacks.pop(), 'a')\n", + "\n", + " print('Test: Pop general case')\n", + " assert_equal(stacks.pop(), 5)\n", + " assert_equal(stacks.pop(), 3)\n", + "\n", + " print('Test: Pop on no elements')\n", + " assert_equal(stacks.pop(), None)\n", + " \n", + " print('Success: test_set_of_stacks')\n", + "\n", + "def main():\n", + " test = TestSetOfStacks()\n", + " test.test_set_of_stacks()\n", + " \n", + "if __name__ == '__main__':\n", + " main()" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Solution Notebook\n", + "\n", + "Review the [Solution Notebook](http://nbviewer.ipython.org/github/donnemartin/coding-challenges/blob/master/stacks_queues/set_of_stacks/set_of_stacks_solution.ipynb) for a discussion on algorithms and code solutions." + ] + } + ], + "metadata": { + "kernelspec": { + "display_name": "Python 2", + "language": "python", + "name": "python2" + }, + "language_info": { + "codemirror_mode": { + "name": "ipython", + "version": 2 + }, + "file_extension": ".py", + "mimetype": "text/x-python", + "name": "python", + "nbconvert_exporter": "python", + "pygments_lexer": "ipython2", + "version": "2.7.10" + } + }, + "nbformat": 4, + "nbformat_minor": 0 +} diff --git a/stacks_queues/set_of_stacks/set_of_stacks_solution.ipynb b/stacks_queues/set_of_stacks/set_of_stacks_solution.ipynb index 2466f53..5dddb58 100644 --- a/stacks_queues/set_of_stacks/set_of_stacks_solution.ipynb +++ b/stacks_queues/set_of_stacks/set_of_stacks_solution.ipynb @@ -4,7 +4,14 @@ "cell_type": "markdown", "metadata": {}, "source": [ - "This notebook was prepared by [Donne Martin](http://donnemartin.com). Source and license info is on [GitHub](https://bit.ly/code-notes)." + "This notebook was prepared by [Donne Martin](http://donnemartin.com). Source and license info is on [GitHub](https://github.com/donnemartin/coding-challenges)." + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "# Solution Notebook" ] }, { @@ -26,7 +33,7 @@ "source": [ "## Constraints\n", "\n", - "*Problem statements are often intentionally ambiguous. Identifying constraints and stating assumptions can help to ensure you code the intended solution.*\n", + "*Problem statements are sometimes ambiguous. Identifying constraints and stating assumptions can help to ensure you code the intended solution.*\n", "\n", "* Can we assume we already have a stack class that can be used for this problem?\n", " * Yes\n", @@ -90,11 +97,11 @@ "cell_type": "code", "execution_count": 1, "metadata": { - "collapsed": true + "collapsed": false }, "outputs": [], "source": [ - "%run stack.py" + "%run ../stack/stack.py" ] }, { @@ -106,6 +113,7 @@ "outputs": [], "source": [ "class StackWithCapacity(Stack):\n", + " \n", " def __init__(self, top=None, capacity=10):\n", " self.capacity = capacity\n", " self.num_items = 0\n", @@ -127,6 +135,7 @@ " return self.num_items == self.capacity\n", "\n", "class SetOfStacks(object):\n", + " \n", " def __init__(self, capacity):\n", " self.capacity = capacity\n", " self.stacks = []\n", @@ -159,8 +168,7 @@ "metadata": {}, "source": [ "## Unit Test\n", - "\n", - "*It is important to identify and run through general and edge cases from the [Test Cases](#Test-Cases) section by hand. You generally will not be asked to write a unit test like what is shown below.*" + "\n" ] }, { @@ -174,20 +182,17 @@ "name": "stdout", "output_type": "stream", "text": [ - "Test: Push on an empty stack\n", - "Test: Push on a non-empty stack\n", - "Test: Push on a capacity stack to create a new one\n", - "Test: Pop on a one element stack to destroy it\n", - "Test: Pop general case\n", - "Test: Pop on no elements\n", - "Success: test_set_of_stacks\n" + "Overwriting test_set_of_stacks.py\n" ] } ], "source": [ + "%%writefile test_set_of_stacks.py\n", "from nose.tools import assert_equal\n", "\n", - "class Test(object):\n", + "\n", + "class TestSetOfStacks(object):\n", + " \n", " def test_set_of_stacks(self):\n", " print('Test: Push on an empty stack')\n", " capacity = 2\n", @@ -212,9 +217,37 @@ " \n", " print('Success: test_set_of_stacks')\n", "\n", + "def main():\n", + " test = TestSetOfStacks()\n", + " test.test_set_of_stacks()\n", + " \n", "if __name__ == '__main__':\n", - " test = Test()\n", - " test.test_set_of_stacks()" + " main()" + ] + }, + { + "cell_type": "code", + "execution_count": 4, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "Test: Push on an empty stack\n", + "Test: Push on a non-empty stack\n", + "Test: Push on a capacity stack to create a new one\n", + "Test: Pop on a one element stack to destroy it\n", + "Test: Pop general case\n", + "Test: Pop on no elements\n", + "Success: test_set_of_stacks\n" + ] + } + ], + "source": [ + "%run -i test_set_of_stacks.py" ] } ], diff --git a/stacks_queues/set_of_stacks/test_set_of_stacks.py b/stacks_queues/set_of_stacks/test_set_of_stacks.py new file mode 100644 index 0000000..88dd30b --- /dev/null +++ b/stacks_queues/set_of_stacks/test_set_of_stacks.py @@ -0,0 +1,35 @@ +from nose.tools import assert_equal + + +class TestSetOfStacks(object): + + def test_set_of_stacks(self): + print('Test: Push on an empty stack') + capacity = 2 + stacks = SetOfStacks(capacity) + 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 one element stack to destroy it') + assert_equal(stacks.pop(), 'a') + + print('Test: Pop general case') + assert_equal(stacks.pop(), 5) + assert_equal(stacks.pop(), 3) + + print('Test: Pop on no elements') + assert_equal(stacks.pop(), None) + + print('Success: test_set_of_stacks') + +def main(): + test = TestSetOfStacks() + test.test_set_of_stacks() + +if __name__ == '__main__': + main() \ No newline at end of file