{ "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/interactive-coding-challenges)." ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "# Challenge Notebook" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Problem: Implement fibonacci recursively, dynamically, and iteratively.\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", "* Does the sequence start at 0 or 1?\n", " * 0\n", "* Can we assume the inputs are valid non-negative ints?\n", " * Yes\n", "* Are you looking for a recursive or iterative solution?\n", " * Implement both\n", "* Can we assume this fits memory?\n", " * Yes" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Test Cases\n", "\n", "* n = 0 -> 0\n", "* n = 1 -> 1\n", "* n = 6 -> 8\n", "* Fib sequence: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34..." ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Algorithm\n", "\n", "Refer to the [Solution Notebook](http://nbviewer.ipython.org/github/donnemartin/interactive-coding-challenges/blob/master/recursion_dynamic/fibonacci/fibonacci_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": true }, "outputs": [], "source": [ "class Math(object):\n", "\n", " def fib_iterative(self, n):\n", " # TODO: Implement me\n", " pass\n", "\n", " def fib_recursive(self, n):\n", " # TODO: Implement me\n", " pass\n", "\n", " def fib_dynamic(self, n):\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": {}, "outputs": [], "source": [ "# %load test_fibonacci.py\n", "import unittest\n", "\n", "\n", "class TestFib(unittest.TestCase):\n", "\n", " def test_fib(self, func):\n", " result = []\n", " expected = [0, 1, 1, 2, 3, 5, 8, 13, 21, 34]\n", " for i in range(len(expected)):\n", " result.append(func(i))\n", " self.assertEqual(result, expected)\n", " print('Success: test_fib')\n", "\n", "\n", "def main():\n", " test = TestFib()\n", " math = Math()\n", " test.test_fib(math.fib_recursive)\n", " test.test_fib(math.fib_dynamic)\n", " test.test_fib(math.fib_iterative)\n", "\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/interactive-coding-challenges/blob/master/recursion_dynamic/fibonacci/fibonacci_solution.ipynb) 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": "3.7.2" } }, "nbformat": 4, "nbformat_minor": 1 }