{ "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: Implement Fizz Buzz.\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", "* What is fizz buzz?\n", " * Return the string representation of numbers from 1 to n\n", " * Multiples of 3 -> 'Fizz'\n", " * Multiples of 5 -> 'Buzz'\n", " * Multiples of 3 and 5 -> 'FizzBuzz'\n", "* Can we assume the inputs are valid?\n", " * No\n", "* Can we assume this fits memory?\n", " * Yes" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Test Cases\n", "\n", "
\n", "* None -> Exception\n", "* < 1 -> Exception\n", "* 15 ->\n", "[\n", " '1',\n", " '2',\n", " 'Fizz',\n", " '4',\n", " 'Buzz',\n", " 'Fizz',\n", " '7',\n", " '8',\n", " 'Fizz',\n", " 'Buzz',\n", " '11',\n", " 'Fizz',\n", " '13',\n", " '14',\n", " 'FizzBuzz'\n", "]\n", "" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Algorithm\n", "\n", "There is no fancy algorithm to solve fizz buzz.\n", "\n", "* Iterate from 1 through n\n", "* Use the mod operator to determine if the current iteration is divisible by:\n", " * 3 and 5 -> 'FizzBuzz'\n", " * 3 -> 'Fizz'\n", " * 5 -> 'Buzz'\n", " * else -> string of current iteration\n", "* return the results\n", "\n", "Complexity:\n", "* Time: O(n)\n", "* Space: O(n)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Code" ] }, { "cell_type": "code", "execution_count": 1, "metadata": { "collapsed": false }, "outputs": [], "source": [ "class Solution(object):\n", "\n", " def fizz_buzz(self, num):\n", " if num is None:\n", " raise TypeError('num cannot be None')\n", " if num < 1:\n", " raise ValueError('num cannot be less than one')\n", " results = []\n", " for i in range(1, num + 1):\n", " if i % 3 == 0 and i % 5 == 0:\n", " results.append('FizzBuzz')\n", " elif i % 3 == 0:\n", " results.append('Fizz')\n", " elif i % 5 == 0:\n", " results.append('Buzz')\n", " else:\n", " results.append(str(i))\n", " return results" ] }, { "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_fizz_buzz.py\n" ] } ], "source": [ "%%writefile test_fizz_buzz.py\n", "from nose.tools import assert_equal, assert_raises\n", "\n", "\n", "class TestFizzBuzz(object):\n", "\n", " def test_fizz_buzz(self):\n", " solution = Solution()\n", " assert_raises(TypeError, solution.fizz_buzz, None)\n", " assert_raises(ValueError, solution.fizz_buzz, 0)\n", " expected = [\n", " '1',\n", " '2',\n", " 'Fizz',\n", " '4',\n", " 'Buzz',\n", " 'Fizz',\n", " '7',\n", " '8',\n", " 'Fizz',\n", " 'Buzz',\n", " '11',\n", " 'Fizz',\n", " '13',\n", " '14',\n", " 'FizzBuzz'\n", " ]\n", " assert_equal(solution.fizz_buzz(15), expected)\n", " print('Success: test_fizz_buzz')\n", "\n", "\n", "def main():\n", " test = TestFizzBuzz()\n", " test.test_fizz_buzz()\n", "\n", "\n", "if __name__ == '__main__':\n", " main()" ] }, { "cell_type": "code", "execution_count": 3, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Success: test_fizz_buzz\n" ] } ], "source": [ "%run -i test_fizz_buzz.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": "3.4.3" } }, "nbformat": 4, "nbformat_minor": 0 }