diff --git a/graphs_trees/trie/__init__.py b/graphs_trees/trie/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/graphs_trees/trie/test_trie.py b/graphs_trees/trie/test_trie.py
new file mode 100644
index 0000000..a0c1bdf
--- /dev/null
+++ b/graphs_trees/trie/test_trie.py
@@ -0,0 +1,74 @@
+from nose.tools import assert_true
+from nose.tools import raises
+
+
+class TestTrie(object):
+
+ def test_trie(self):
+ trie = Trie()
+
+ print('Test: Insert')
+ words = ['a', 'at', 'has', 'hat', 'he',
+ 'me', 'men', 'mens', 'met']
+ for word in words:
+ trie.insert(word)
+ for word in trie.list_words():
+ assert_true(trie.find(word) is not None)
+
+ print('Test: Remove me')
+ trie.remove('me')
+ words_removed = ['me']
+ words = ['a', 'at', 'has', 'hat', 'he',
+ 'men', 'mens', 'met']
+ for word in words:
+ assert_true(trie.find(word) is not None)
+ for word in words_removed:
+ assert_true(trie.find(word) is None)
+
+ print('Test: Remove mens')
+ trie.remove('mens')
+ words_removed = ['me', 'mens']
+ words = ['a', 'at', 'has', 'hat', 'he',
+ 'men', 'met']
+ for word in words:
+ assert_true(trie.find(word) is not None)
+ for word in words_removed:
+ assert_true(trie.find(word) is None)
+
+ print('Test: Remove a')
+ trie.remove('a')
+ words_removed = ['a', 'me', 'mens']
+ words = ['at', 'has', 'hat', 'he',
+ 'men', 'met']
+ for word in words:
+ assert_true(trie.find(word) is not None)
+ for word in words_removed:
+ assert_true(trie.find(word) is None)
+
+ print('Test: Remove has')
+ trie.remove('has')
+ words_removed = ['a', 'has', 'me', 'mens']
+ words = ['at', 'hat', 'he',
+ 'men', 'met']
+ for word in words:
+ assert_true(trie.find(word) is not None)
+ for word in words_removed:
+ assert_true(trie.find(word) is None)
+
+ print('Success: test_trie')
+
+ @raises(Exception)
+ def test_trie_remove_invalid(self):
+ print('Test: Remove from empty trie')
+ trie = Trie()
+ assert_true(trie.remove('foo') is None)
+
+
+def main():
+ test = TestTrie()
+ test.test_trie()
+ test.test_trie_remove_invalid()
+
+
+if __name__ == '__main__':
+ main()
\ No newline at end of file
diff --git a/graphs_trees/trie/trie.py b/graphs_trees/trie/trie.py
new file mode 100644
index 0000000..7cfe0fa
--- /dev/null
+++ b/graphs_trees/trie/trie.py
@@ -0,0 +1,76 @@
+from collections import OrderedDict
+
+
+class Node(object):
+
+ def __init__(self, key, parent=None, terminates=False):
+ self.key = key
+ self.terminates = False
+ self.parent = parent
+ self.children = {}
+
+
+class Trie(object):
+
+ def __init__(self):
+ self.root = Node('')
+
+ def find(self, word):
+ if word is None:
+ raise TypeError('word cannot be None')
+ node = self.root
+ for char in word:
+ if char in node.children:
+ node = node.children[char]
+ else:
+ return None
+ return node if node.terminates else None
+
+ def insert(self, word):
+ if word is None:
+ raise TypeError('word cannot be None')
+ node = self.root
+ parent = None
+ for char in word:
+ if char in node.children:
+ node = node.children[char]
+ else:
+ node.children[char] = Node(char, parent=node)
+ node = node.children[char]
+ node.terminates = True
+
+ def remove(self, word):
+ if word is None:
+ raise TypeError('word cannot be None')
+ node = self.find(word)
+ if node is None:
+ raise KeyError('word does not exist')
+ node.terminates = False
+ parent = node.parent
+ while parent is not None:
+ # As we are propagating the delete up the
+ # parents, if this node has children, stop
+ # here to prevent orphaning its children.
+ # Or
+ # if this node is a terminating node that is
+ # not the terminating node of the input word,
+ # stop to prevent removing the associated word.
+ if node.children or node.terminates:
+ return
+ del parent.children[node.key]
+ node = parent
+ parent = parent.parent
+
+ def list_words(self):
+ result = []
+ curr_word = ''
+ self._list_words(self.root, curr_word, result)
+ return result
+
+ def _list_words(self, node, curr_word, result):
+ if node is None:
+ return
+ for key, child in node.children.items():
+ if child.terminates:
+ result.append(curr_word+key)
+ self._list_words(child, curr_word+key, result)
\ No newline at end of file
diff --git a/graphs_trees/trie/trie_challenge.ipynb b/graphs_trees/trie/trie_challenge.ipynb
new file mode 100644
index 0000000..8889146
--- /dev/null
+++ b/graphs_trees/trie/trie_challenge.ipynb
@@ -0,0 +1,279 @@
+{
+ "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: Implement a trie with find, insert, remove, and list_words methods.\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 are working with strings?\n",
+ " * Yes\n",
+ "* Are the strings in ASCII?\n",
+ " * Yes\n",
+ "* Should `find` only match exact words with a terminating character?\n",
+ " * Yes\n",
+ "* Should `list_words` only return words with a terminating character?\n",
+ " * Yes\n",
+ "* Can we assume this fits memory?\n",
+ " * Yes"
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "## Test Cases\n",
+ "\n",
+ "\n",
+ "\n",
+ " root\n",
+ " / | \\\n",
+ " h a* m\n",
+ " / \\ \\ \\\n",
+ " a e* t* e*\n",
+ " / \\ / \\\n",
+ " s* t* n* t*\n",
+ " /\n",
+ " s*\n",
+ "\n",
+ "find\n",
+ "\n",
+ "* Find on an empty trie\n",
+ "* Find non-matching\n",
+ "* Find matching\n",
+ "\n",
+ "insert\n",
+ "\n",
+ "* Insert on empty trie\n",
+ "* Insert to make a leaf terminator char\n",
+ "* Insert to extend an existing terminator char\n",
+ "\n",
+ "remove\n",
+ "\n",
+ "* Remove me\n",
+ "* Remove mens\n",
+ "* Remove a\n",
+ "* Remove has\n",
+ "\n",
+ "list_words\n",
+ "\n",
+ "* List empty\n",
+ "* List general case\n",
+ "
\n",
+ "\n"
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "## Algorithm\n",
+ "\n",
+ "Refer to the [Solution Notebook](http://nbviewer.ipython.org/github/donnemartin/interactive-coding-challenges/blob/master/graphs_trees/trie/trie_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": [
+ "from collections import OrderedDict\n",
+ "\n",
+ "\n",
+ "class Node(object):\n",
+ "\n",
+ " def __init__(self, data, parent=None, terminates=False):\n",
+ " # TODO: Implement me\n",
+ " pass\n",
+ "\n",
+ "\n",
+ "class Trie(object):\n",
+ "\n",
+ " def __init__(self):\n",
+ " # TODO: Implement me\n",
+ " pass\n",
+ "\n",
+ " def find(self, word):\n",
+ " # TODO: Implement me\n",
+ " pass\n",
+ "\n",
+ " def insert(self, word):\n",
+ " # TODO: Implement me\n",
+ " pass\n",
+ "\n",
+ " def remove(self, word):\n",
+ " # TODO: Implement me\n",
+ " pass\n",
+ "\n",
+ " def list_words(self):\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_trie.py\n",
+ "from nose.tools import assert_true\n",
+ "\n",
+ "\n",
+ "class TestTrie(object):\n",
+ "\n",
+ " def test_trie(self):\n",
+ " print('Test: Remove from empty trie')\n",
+ " trie = Trie()\n",
+ " assert_true(trie.remove('foo') is None)\n",
+ "\n",
+ " print('Test: Insert')\n",
+ " words = ['a', 'at', 'has', 'hat', 'he',\n",
+ " 'me', 'men', 'mens', 'met']\n",
+ " for word in words:\n",
+ " trie.insert(word)\n",
+ " for word in trie.list_words():\n",
+ " assert_true(trie.find(word) is not None)\n",
+ "\n",
+ " # Remove me\n",
+ " # Remove mens\n",
+ " # Remove a\n",
+ " \n",
+ " print('Test: Remove me')\n",
+ " trie.remove('me')\n",
+ " words_removed = ['me']\n",
+ " words = ['a', 'at', 'has', 'hat', 'he',\n",
+ " 'men', 'mens', 'met']\n",
+ " for word in words:\n",
+ " assert_true(trie.find(word) is not None)\n",
+ " for word in words_removed:\n",
+ " assert_true(trie.find(word) is None)\n",
+ "\n",
+ " print('Test: Remove mens')\n",
+ " trie.remove('mens')\n",
+ " words_removed = ['me', 'mens']\n",
+ " words = ['a', 'at', 'has', 'hat', 'he',\n",
+ " 'men', 'met']\n",
+ " for word in words:\n",
+ " assert_true(trie.find(word) is not None)\n",
+ " for word in words_removed:\n",
+ " assert_true(trie.find(word) is None)\n",
+ "\n",
+ " print('Test: Remove a')\n",
+ " trie.remove('a')\n",
+ " words_removed = ['a', 'me', 'mens']\n",
+ " words = ['at', 'has', 'hat', 'he',\n",
+ " 'men', 'met']\n",
+ " for word in words:\n",
+ " assert_true(trie.find(word) is not None)\n",
+ " for word in words_removed:\n",
+ " assert_true(trie.find(word) is None)\n",
+ "\n",
+ " print('Test: Remove has')\n",
+ " trie.remove('has')\n",
+ " words_removed = ['a', 'has', 'me', 'mens']\n",
+ " words = ['at', 'hat', 'he',\n",
+ " 'men', 'met']\n",
+ " for word in words:\n",
+ " assert_true(trie.find(word) is not None)\n",
+ " for word in words_removed:\n",
+ " assert_true(trie.find(word) is None)\n",
+ "\n",
+ " print('Success: test_trie')\n",
+ "\n",
+ "\n",
+ "def main():\n",
+ " test = TestTrie()\n",
+ " test.test_trie()\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/graphs_trees/trie/trie_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": "3.5.0"
+ }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/graphs_trees/trie/trie_solution.ipynb b/graphs_trees/trie/trie_solution.ipynb
new file mode 100644
index 0000000..aec6ba2
--- /dev/null
+++ b/graphs_trees/trie/trie_solution.ipynb
@@ -0,0 +1,418 @@
+{
+ "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 a trie with find, insert, remove, and list_words methods.\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 are working with strings?\n",
+ " * Yes\n",
+ "* Are the strings in ASCII?\n",
+ " * Yes\n",
+ "* Should `find` only match exact words with a terminating character?\n",
+ " * Yes\n",
+ "* Should `list_words` only return words with a terminating character?\n",
+ " * Yes\n",
+ "* Can we assume this fits memory?\n",
+ " * Yes"
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "## Test Cases\n",
+ "\n",
+ "\n",
+ "\n",
+ "root node is denoted by ''\n",
+ "\n",
+ " ''\n",
+ " / | \\\n",
+ " h a* m\n",
+ " / \\ \\ \\\n",
+ " a e* t* e*\n",
+ " / \\ / \\\n",
+ " s* t* n* t*\n",
+ " /\n",
+ " s*\n",
+ "\n",
+ "find\n",
+ "\n",
+ "* Find on an empty trie\n",
+ "* Find non-matching\n",
+ "* Find matching\n",
+ "\n",
+ "insert\n",
+ "\n",
+ "* Insert on empty trie\n",
+ "* Insert to make a leaf terminator char\n",
+ "* Insert to extend an existing terminator char\n",
+ "\n",
+ "remove\n",
+ "\n",
+ "* Remove me\n",
+ "* Remove mens\n",
+ "* Remove a\n",
+ "* Remove has\n",
+ "\n",
+ "list_words\n",
+ "\n",
+ "* List empty\n",
+ "* List general case\n",
+ "
\n",
+ "\n",
+ "\n"
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "## Algorithm\n",
+ "\n",
+ "### find\n",
+ "\n",
+ "* Set node to the root\n",
+ "* For each char in the input word\n",
+ " * Check the current node's children to see if it contains the char\n",
+ " * If a child has the char, set node to the child\n",
+ " * Else, return None\n",
+ "* Return the last child node if it has a terminator, else None\n",
+ "\n",
+ "Complexity:\n",
+ "* Time: O(m), where m is the length of the word\n",
+ "* Space: O(h) for the recursion depth (tree height), or O(1) if using an iterative approach\n",
+ "\n",
+ "### insert\n",
+ "\n",
+ "* set node to the root\n",
+ "* For each char in the input word\n",
+ " * Check the current node's children to see if it contains the char\n",
+ " * If a child has the char, set node to the child\n",
+ " * Else, insert a new node with the char\n",
+ " * Update children and parents\n",
+ "* Set the last node as a terminating node\n",
+ "\n",
+ "Complexity:\n",
+ "* Time: O(m), where m is the length of the word\n",
+ "* Space: O(h) for the recursion depth (tree height), or O(1) if using an iterative approach\n",
+ "\n",
+ "### remove\n",
+ "\n",
+ "* Determine the matching terminating node by calling the find method\n",
+ "* If the matching node has children, remove the terminator to prevent orphaning its children\n",
+ "* Set the parent node to the matching node's parent\n",
+ "* We'll be looping up the parent chain to propagate the delete\n",
+ "* While the parent is valid\n",
+ " * If the node has children\n",
+ " * Return to prevent orphaning its remaining children\n",
+ " * If the node is a terminating node and it isn't the original matching node from the find call\n",
+ " * Return to prevent deleting this additional valid word\n",
+ " * Remove the parent node's child entry matching the node\n",
+ " * Set the node to the parent\n",
+ " * Set the parent to the parent's parent\n",
+ "\n",
+ "Complexity:\n",
+ "* Time: O(m+h), where where m is the length of the word and h is the tree height\n",
+ "* Space: O(h) for the recursion depth (tree height), or O(1) if using an iterative approach\n",
+ "\n",
+ "### list_words\n",
+ "\n",
+ "* Do a pre-order traversal, passing down the current word\n",
+ " * When you reach a terminating node, add it to the list of results\n",
+ "\n",
+ "Complexity:\n",
+ "* Time: O(n)\n",
+ "* Space: O(h) for the recursion depth (tree height), or O(1) if using an iterative approach"
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "## Code"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 1,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "Overwriting trie.py\n"
+ ]
+ }
+ ],
+ "source": [
+ "%%writefile trie.py\n",
+ "from collections import OrderedDict\n",
+ "\n",
+ "\n",
+ "class Node(object):\n",
+ "\n",
+ " def __init__(self, key, parent=None, terminates=False):\n",
+ " self.key = key\n",
+ " self.terminates = False\n",
+ " self.parent = parent\n",
+ " self.children = {}\n",
+ "\n",
+ "\n",
+ "class Trie(object):\n",
+ "\n",
+ " def __init__(self):\n",
+ " self.root = Node('')\n",
+ "\n",
+ " def find(self, word):\n",
+ " if word is None:\n",
+ " raise TypeError('word cannot be None')\n",
+ " node = self.root\n",
+ " for char in word:\n",
+ " if char in node.children:\n",
+ " node = node.children[char]\n",
+ " else:\n",
+ " return None\n",
+ " return node if node.terminates else None\n",
+ "\n",
+ " def insert(self, word):\n",
+ " if word is None:\n",
+ " raise TypeError('word cannot be None')\n",
+ " node = self.root\n",
+ " parent = None\n",
+ " for char in word:\n",
+ " if char in node.children:\n",
+ " node = node.children[char]\n",
+ " else:\n",
+ " node.children[char] = Node(char, parent=node)\n",
+ " node = node.children[char]\n",
+ " node.terminates = True\n",
+ "\n",
+ " def remove(self, word):\n",
+ " if word is None:\n",
+ " raise TypeError('word cannot be None')\n",
+ " node = self.find(word)\n",
+ " if node is None:\n",
+ " raise KeyError('word does not exist')\n",
+ " node.terminates = False\n",
+ " parent = node.parent\n",
+ " while parent is not None:\n",
+ " # As we are propagating the delete up the \n",
+ " # parents, if this node has children, stop\n",
+ " # here to prevent orphaning its children.\n",
+ " # Or\n",
+ " # if this node is a terminating node that is\n",
+ " # not the terminating node of the input word, \n",
+ " # stop to prevent removing the associated word.\n",
+ " if node.children or node.terminates:\n",
+ " return\n",
+ " del parent.children[node.key]\n",
+ " node = parent\n",
+ " parent = parent.parent\n",
+ "\n",
+ " def list_words(self):\n",
+ " result = []\n",
+ " curr_word = ''\n",
+ " self._list_words(self.root, curr_word, result)\n",
+ " return result\n",
+ "\n",
+ " def _list_words(self, node, curr_word, result):\n",
+ " if node is None:\n",
+ " return\n",
+ " for key, child in node.children.items():\n",
+ " if child.terminates:\n",
+ " result.append(curr_word + key)\n",
+ " self._list_words(child, curr_word + key, result)"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 2,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [],
+ "source": [
+ "%run trie.py"
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "## Unit Test"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 3,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "Overwriting test_trie.py\n"
+ ]
+ }
+ ],
+ "source": [
+ "%%writefile test_trie.py\n",
+ "from nose.tools import assert_true\n",
+ "from nose.tools import raises\n",
+ "\n",
+ "\n",
+ "class TestTrie(object): \n",
+ "\n",
+ " def test_trie(self):\n",
+ " trie = Trie()\n",
+ "\n",
+ " print('Test: Insert')\n",
+ " words = ['a', 'at', 'has', 'hat', 'he',\n",
+ " 'me', 'men', 'mens', 'met']\n",
+ " for word in words:\n",
+ " trie.insert(word)\n",
+ " for word in trie.list_words():\n",
+ " assert_true(trie.find(word) is not None)\n",
+ " \n",
+ " print('Test: Remove me')\n",
+ " trie.remove('me')\n",
+ " words_removed = ['me']\n",
+ " words = ['a', 'at', 'has', 'hat', 'he',\n",
+ " 'men', 'mens', 'met']\n",
+ " for word in words:\n",
+ " assert_true(trie.find(word) is not None)\n",
+ " for word in words_removed:\n",
+ " assert_true(trie.find(word) is None)\n",
+ "\n",
+ " print('Test: Remove mens')\n",
+ " trie.remove('mens')\n",
+ " words_removed = ['me', 'mens']\n",
+ " words = ['a', 'at', 'has', 'hat', 'he',\n",
+ " 'men', 'met']\n",
+ " for word in words:\n",
+ " assert_true(trie.find(word) is not None)\n",
+ " for word in words_removed:\n",
+ " assert_true(trie.find(word) is None)\n",
+ "\n",
+ " print('Test: Remove a')\n",
+ " trie.remove('a')\n",
+ " words_removed = ['a', 'me', 'mens']\n",
+ " words = ['at', 'has', 'hat', 'he',\n",
+ " 'men', 'met']\n",
+ " for word in words:\n",
+ " assert_true(trie.find(word) is not None)\n",
+ " for word in words_removed:\n",
+ " assert_true(trie.find(word) is None)\n",
+ "\n",
+ " print('Test: Remove has')\n",
+ " trie.remove('has')\n",
+ " words_removed = ['a', 'has', 'me', 'mens']\n",
+ " words = ['at', 'hat', 'he',\n",
+ " 'men', 'met']\n",
+ " for word in words:\n",
+ " assert_true(trie.find(word) is not None)\n",
+ " for word in words_removed:\n",
+ " assert_true(trie.find(word) is None)\n",
+ "\n",
+ " print('Success: test_trie')\n",
+ "\n",
+ " @raises(Exception)\n",
+ " def test_trie_remove_invalid(self):\n",
+ " print('Test: Remove from empty trie')\n",
+ " trie = Trie()\n",
+ " assert_true(trie.remove('foo') is None) \n",
+ "\n",
+ "\n",
+ "def main():\n",
+ " test = TestTrie()\n",
+ " test.test_trie()\n",
+ " test.test_trie_remove_invalid()\n",
+ "\n",
+ "\n",
+ "if __name__ == '__main__':\n",
+ " main()"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 4,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "Test: Insert\n",
+ "Test: Remove me\n",
+ "Test: Remove mens\n",
+ "Test: Remove a\n",
+ "Test: Remove has\n",
+ "Success: test_trie\n",
+ "Test: Remove from empty trie\n"
+ ]
+ }
+ ],
+ "source": [
+ "%run -i test_trie.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
+}