interactive-coding-challenges/arrays_strings/unique_chars/unique_chars_challenge.ipynb

174 lines
4.4 KiB
Python

{
"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 an algorithm to determine if a string has all unique characters.\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 the string is ASCII?\n",
" * Yes\n",
" * Note: Unicode strings could require special handling depending on your language\n",
"* Can we assume this is case sensitive?\n",
" * Yes\n",
"* Can we use additional data structures?\n",
" * Yes\n",
"* Can we assume this fits in memory?\n",
" * Yes"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Test Cases\n",
"\n",
"* None -> False\n",
"* '' -> True\n",
"* 'foo' -> False\n",
"* 'bar' -> True"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Algorithm\n",
"\n",
"Refer to the [Solution Notebook](http://nbviewer.ipython.org/github/donnemartin/interactive-coding-challenges/blob/master/arrays_strings/unique_chars/unique_chars_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": {},
"outputs": [],
"source": [
"class UniqueChars(object):\n",
"\n",
" def has_unique_chars(self, string):\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": {},
"outputs": [],
"source": [
"# %load test_unique_chars.py\n",
"import unittest\n",
"\n",
"\n",
"class TestUniqueChars(unittest.TestCase):\n",
"\n",
" def test_unique_chars(self, func):\n",
" self.assertEqual(func(None), False)\n",
" self.assertEqual(func(''), True)\n",
" self.assertEqual(func('foo'), False)\n",
" self.assertEqual(func('bar'), True)\n",
" print('Success: test_unique_chars')\n",
"\n",
"\n",
"def main():\n",
" test = TestUniqueChars()\n",
" unique_chars = UniqueChars()\n",
" test.test_unique_chars(unique_chars.has_unique_chars)\n",
" try:\n",
" unique_chars_set = UniqueCharsSet()\n",
" test.test_unique_chars(unique_chars_set.has_unique_chars)\n",
" unique_chars_in_place = UniqueCharsInPlace()\n",
" test.test_unique_chars(unique_chars_in_place.has_unique_chars)\n",
" except NameError:\n",
" # Alternate solutions are only defined\n",
" # in the solutions file\n",
" pass\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/arrays_strings/unique_chars/unique_chars_solution.ipynb) for a discussion on algorithms and code solutions."
]
}
],
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"display_name": "Python 3",
"language": "python",
"name": "python3"
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"file_extension": ".py",
"mimetype": "text/x-python",
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