From f469ccd0888f5c79e456d9eb1f7cc6475b56de8a Mon Sep 17 00:00:00 2001 From: Donne Martin Date: Tue, 28 Mar 2017 05:10:39 -0400 Subject: [PATCH] Add sum two challenge --- online_judges/sum_two/sum_two_challenge.ipynb | 164 +++++++++++++ online_judges/sum_two/sum_two_solution.ipynb | 225 ++++++++++++++++++ online_judges/sum_two/test_sum_two.py | 21 ++ 3 files changed, 410 insertions(+) create mode 100644 online_judges/sum_two/sum_two_challenge.ipynb create mode 100644 online_judges/sum_two/sum_two_solution.ipynb create mode 100644 online_judges/sum_two/test_sum_two.py diff --git a/online_judges/sum_two/sum_two_challenge.ipynb b/online_judges/sum_two/sum_two_challenge.ipynb new file mode 100644 index 0000000..bf48578 --- /dev/null +++ b/online_judges/sum_two/sum_two_challenge.ipynb @@ -0,0 +1,164 @@ +{ + "cells": [ + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "This notebook was prepared by [Donne Martin](https://github.com/donnemartin). Source and license info is on [GitHub](https://github.com/donnemartin/interactive-coding-challenges)." + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "# Challenge Notebook" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Problem: Sum of Two Integers.\n", + "\n", + "See the [LeetCode](https://leetcode.com/problems/sum-of-two-integers/) problem page.\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", + "* Can we assume we're working with 32 bit ints?\n", + " * Yes\n", + "* Can we assume the inputs are valid?\n", + " * No, check for None\n", + "* Can we assume this fits memory?\n", + " * Yes" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Test Cases\n", + "\n", + "See the [LeetCode](https://leetcode.com/problems/sum-of-two-integers/) problem page." + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Algorithm\n", + "\n", + "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." + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Code" + ] + }, + { + "cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": false + }, + "outputs": [], + "source": [ + "class Solution(object):\n", + "\n", + " def sum_two(self, val):\n", + " # TODO: Implement me\n", + " pass" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Unit Test" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "**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_sum_two.py\n", + "from nose.tools import assert_equal, assert_raises\n", + "\n", + "\n", + "class TestSumTwo(object):\n", + "\n", + " def test_sum_two(self):\n", + " solution = Solution()\n", + " assert_raises(TypeError, solution.sum_two, None)\n", + " assert_equal(solution.sum_two(5, 7), 12)\n", + " assert_equal(solution.sum_two(-5, -7), -12)\n", + " assert_equal(solution.sum_two(5, -7), -2)\n", + " print('Success: test_sum_two')\n", + "\n", + "\n", + "def main():\n", + " test = TestSumTwo()\n", + " test.test_sum_two()\n", + "\n", + "\n", + "if __name__ == '__main__':\n", + " main()" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Solution Notebook\n", + "\n", + "Review the [Solution Notebook]() for a discussion on algorithms and code solutions." + ] + } + ], + "metadata": { + "kernelspec": { + "display_name": "Python 3", + "language": "python", + "name": "python3" + }, + "language_info": { + "codemirror_mode": { + "name": "ipython", + "version": 3 + }, + "file_extension": ".py", + "mimetype": "text/x-python", + "name": "python", + "nbconvert_exporter": "python", + "pygments_lexer": "ipython3", + "version": "3.5.0" + } + }, + "nbformat": 4, + "nbformat_minor": 0 +} diff --git a/online_judges/sum_two/sum_two_solution.ipynb b/online_judges/sum_two/sum_two_solution.ipynb new file mode 100644 index 0000000..e25fe50 --- /dev/null +++ b/online_judges/sum_two/sum_two_solution.ipynb @@ -0,0 +1,225 @@ +{ + "cells": [ + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "This notebook was prepared by [Donne Martin](https://github.com/donnemartin). Source and license info is on [GitHub](https://github.com/donnemartin/interactive-coding-challenges)." + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "# Solution Notebook" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Problem: Sum of Two Integers.\n", + "\n", + "See the [LeetCode](https://leetcode.com/problems/sum-of-two-integers/) problem page.\n", + "\n", + "* [Constraints](#Constraints)\n", + "* [Test Cases](#Test-Cases)\n", + "* [Algorithm](#Algorithm)\n", + "* [Code](#Code)\n", + "* [Unit Test](#Unit-Test)" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Constraints\n", + "\n", + "* Can we assume we're working with 32 bit ints?\n", + " * Yes\n", + "* Can we assume the inputs are valid?\n", + " * No, check for None\n", + "* Can we assume this fits memory?\n", + " * Yes" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Test Cases\n", + "\n", + "
\n",
+    "* None input -> TypeError\n",
+    "* 5, 7 -> 12\n",
+    "* -5, -7 -> -12\n",
+    "* 5, -7 -> -2\n",
+    "
" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Algorithm\n", + "\n", + "We'll look at the following example, adding a and b:\n", + "\n", + "
\n",
+    "a 0111 \n",
+    "b 0101\n",
+    "
\n", + "\n", + "First, add a and b, without worrying about the carry (0+0=0, 0+1=1, 1+1=0):\n", + "\n", + "result = a ^ b = 0010\n", + "\n", + "Next, calculate the carry (1+1=2). We'll need to left shift one to prepare for the next iteration when we move to the next most significant bit:\n", + "\n", + "carry = (a&b) << 1 = 1010\n", + "\n", + "If the carry is not zero, we'll need to add the carry to the result. Recusively call the function, passing in result and carry.\n", + "\n", + "Below are the values of a, b, and the carry of a = 7 and b = 5, producing the result of 12.\n", + "\n", + "
\n",
+    "a 0111 \n",
+    "b 0101 \n",
+    "----- \n",
+    "c 0101 \n",
+    "a 0010 \n",
+    "b 1010 \n",
+    "----- \n",
+    "c 0010 \n",
+    "a 1000 \n",
+    "b 0100 \n",
+    "----- \n",
+    "c 0000 \n",
+    "a 1100 \n",
+    "b 0000\n",
+    "\n",
+    "c = carry = 0, return the result 1100\n",
+    "
\n", + "\n", + "Complexity:\n", + "* Time: O(b), where b is the number of bits\n", + "* Space: O(b), where b is the number of bits" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Code" + ] + }, + { + "cell_type": "code", + "execution_count": 1, + "metadata": { + "collapsed": false + }, + "outputs": [], + "source": [ + "class Solution(object):\n", + "\n", + " def sum_two(self, a, b):\n", + " if a is None or b is None:\n", + " raise TypeError('a or b cannot be None')\n", + " result = a ^ b;\n", + " carry = (a&b) << 1\n", + " if carry != 0:\n", + " return self.sum_two(result, carry)\n", + " return result;" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Unit Test" + ] + }, + { + "cell_type": "code", + "execution_count": 2, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "Overwriting test_sum_two.py\n" + ] + } + ], + "source": [ + "%%writefile test_sum_two.py\n", + "from nose.tools import assert_equal, assert_raises\n", + "\n", + "\n", + "class TestSumTwo(object):\n", + "\n", + " def test_sum_two(self):\n", + " solution = Solution()\n", + " assert_raises(TypeError, solution.sum_two, None)\n", + " assert_equal(solution.sum_two(5, 7), 12)\n", + " assert_equal(solution.sum_two(-5, -7), -12)\n", + " assert_equal(solution.sum_two(5, -7), -2)\n", + " print('Success: test_sum_two')\n", + "\n", + "\n", + "def main():\n", + " test = TestSumTwo()\n", + " test.test_sum_two()\n", + "\n", + "\n", + "if __name__ == '__main__':\n", + " main()" + ] + }, + { + "cell_type": "code", + "execution_count": 3, + "metadata": { + "collapsed": false, + "scrolled": true + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "Success: test_sum_two\n" + ] + } + ], + "source": [ + "%run -i test_sum_two.py" + ] + } + ], + "metadata": { + "kernelspec": { + "display_name": "Python 3", + "language": "python", + "name": "python3" + }, + "language_info": { + "codemirror_mode": { + "name": "ipython", + "version": 3 + }, + "file_extension": ".py", + "mimetype": "text/x-python", + "name": "python", + "nbconvert_exporter": "python", + "pygments_lexer": "ipython3", + "version": "3.5.0" + } + }, + "nbformat": 4, + "nbformat_minor": 0 +} diff --git a/online_judges/sum_two/test_sum_two.py b/online_judges/sum_two/test_sum_two.py new file mode 100644 index 0000000..82a5ada --- /dev/null +++ b/online_judges/sum_two/test_sum_two.py @@ -0,0 +1,21 @@ +from nose.tools import assert_equal, assert_raises + + +class TestSumTwo(object): + + def test_sum_two(self): + solution = Solution() + assert_raises(TypeError, solution.sum_two, None) + assert_equal(solution.sum_two(5, 7), 12) + assert_equal(solution.sum_two(-5, -7), -12) + assert_equal(solution.sum_two(5, -7), -2) + print('Success: test_sum_two') + + +def main(): + test = TestSumTwo() + test.test_sum_two() + + +if __name__ == '__main__': + main() \ No newline at end of file