From 31058abf3af37319db45ee7d34c80a78656f9ddc Mon Sep 17 00:00:00 2001 From: Donne Martin Date: Sat, 1 Aug 2015 17:44:14 -0400 Subject: [PATCH] Simpilfied bst challenge. --- graphs_trees/bst/bst.py | 18 ++++++++ graphs_trees/bst/bst_challenge.ipynb | 46 +++++++++++--------- graphs_trees/bst/bst_solution.ipynb | 64 +++++++++++++++------------- graphs_trees/bst/dfs.py | 17 ++++++++ graphs_trees/bst/test_bst.py | 24 +++++------ 5 files changed, 106 insertions(+), 63 deletions(-) create mode 100644 graphs_trees/bst/bst.py create mode 100644 graphs_trees/bst/dfs.py diff --git a/graphs_trees/bst/bst.py b/graphs_trees/bst/bst.py new file mode 100644 index 0000000..ebda949 --- /dev/null +++ b/graphs_trees/bst/bst.py @@ -0,0 +1,18 @@ +class Node(object): + + def __init__(self, data): + self.data = data + self.left = None + self.right = None + +def insert(root, data): + if data <= root.data: + if root.left is None: + root.left = Node(data) + else: + insert(root.left, data) + else: + if root.right is None: + root.right = Node(data) + else: + insert(root.right, data) diff --git a/graphs_trees/bst/bst_challenge.ipynb b/graphs_trees/bst/bst_challenge.ipynb index 9082704..7699f15 100644 --- a/graphs_trees/bst/bst_challenge.ipynb +++ b/graphs_trees/bst/bst_challenge.ipynb @@ -86,15 +86,8 @@ " def __init__(self, data):\n", " # TODO: Implement me\n", "\n", - " def insert(self, data):\n", - " # TODO: Implement me\n", - "\n", - " def in_order_traversal(self, visit_func):\n", - " if self.left is not None:\n", - " self.left.in_order_traversal(visit_func)\n", - " visit_func(self.data)\n", - " if self.right is not None:\n", - " self.right.in_order_traversal(visit_func)" + "def insert(root, data):\n", + " # TODO: Implement me" ] }, { @@ -122,6 +115,17 @@ "%run ../utils/captured_output.py" ] }, + { + "cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": true + }, + "outputs": [], + "source": [ + "%run dfs.py" + ] + }, { "cell_type": "code", "execution_count": null, @@ -138,24 +142,24 @@ "class TestTree(object):\n", "\n", " def test_tree(self):\n", - " root = Node(5)\n", - " root.insert(2)\n", - " root.insert(8)\n", - " root.insert(1)\n", - " root.insert(3)\n", + " node = Node(5)\n", + " insert(node, 2)\n", + " insert(node, 8)\n", + " insert(node, 1)\n", + " insert(node, 3)\n", "\n", " with captured_output() as (out, err):\n", - " root.in_order_traversal(sys.stdout.write)\n", + " in_order_traversal(node, sys.stdout.write)\n", " assert_equal(out.getvalue().strip(), '12358')\n", "\n", - " root = Node(1)\n", - " root.insert(2)\n", - " root.insert(3)\n", - " root.insert(4)\n", - " root.insert(5)\n", + " node = Node(1)\n", + " insert(node, 2)\n", + " insert(node, 3)\n", + " insert(node, 4)\n", + " insert(node, 5)\n", "\n", " with captured_output() as (out, err):\n", - " root.in_order_traversal(sys.stdout.write)\n", + " in_order_traversal(node, sys.stdout.write)\n", " assert_equal(out.getvalue().strip(), '12345')\n", "\n", " print('Success: test_tree')\n", diff --git a/graphs_trees/bst/bst_solution.ipynb b/graphs_trees/bst/bst_solution.ipynb index 8d3862b..598266a 100644 --- a/graphs_trees/bst/bst_solution.ipynb +++ b/graphs_trees/bst/bst_solution.ipynb @@ -100,24 +100,17 @@ " self.left = None\n", " self.right = None\n", "\n", - " def insert(self, data):\n", - " if data <= self.data:\n", - " if self.left is None:\n", - " self.left = Node(data)\n", - " else:\n", - " self.left.insert(data)\n", + "def insert(root, data):\n", + " if data <= root.data:\n", + " if root.left is None:\n", + " root.left = Node(data)\n", " else:\n", - " if self.right is None:\n", - " self.right = Node(data)\n", - " else:\n", - " self.right.insert(data)\n", - "\n", - " def in_order_traversal(self, visit_func):\n", - " if self.left is not None:\n", - " self.left.in_order_traversal(visit_func)\n", - " visit_func(self.data)\n", - " if self.right is not None:\n", - " self.right.in_order_traversal(visit_func)" + " insert(root.left, data)\n", + " else:\n", + " if root.right is None:\n", + " root.right = Node(data)\n", + " else:\n", + " insert(root.right, data)" ] }, { @@ -141,6 +134,17 @@ { "cell_type": "code", "execution_count": 3, + "metadata": { + "collapsed": true + }, + "outputs": [], + "source": [ + "%run dfs.py" + ] + }, + { + "cell_type": "code", + "execution_count": 4, "metadata": { "collapsed": false }, @@ -162,24 +166,24 @@ "class TestTree(object):\n", "\n", " def test_tree(self):\n", - " root = Node(5)\n", - " root.insert(2)\n", - " root.insert(8)\n", - " root.insert(1)\n", - " root.insert(3)\n", + " node = Node(5)\n", + " insert(node, 2)\n", + " insert(node, 8)\n", + " insert(node, 1)\n", + " insert(node, 3)\n", "\n", " with captured_output() as (out, err):\n", - " root.in_order_traversal(sys.stdout.write)\n", + " in_order_traversal(node, sys.stdout.write)\n", " assert_equal(out.getvalue().strip(), '12358')\n", "\n", - " root = Node(1)\n", - " root.insert(2)\n", - " root.insert(3)\n", - " root.insert(4)\n", - " root.insert(5)\n", + " node = Node(1)\n", + " insert(node, 2)\n", + " insert(node, 3)\n", + " insert(node, 4)\n", + " insert(node, 5)\n", "\n", " with captured_output() as (out, err):\n", - " root.in_order_traversal(sys.stdout.write)\n", + " in_order_traversal(node, sys.stdout.write)\n", " assert_equal(out.getvalue().strip(), '12345')\n", "\n", " print('Success: test_tree')\n", @@ -196,7 +200,7 @@ }, { "cell_type": "code", - "execution_count": 4, + "execution_count": 5, "metadata": { "collapsed": false }, diff --git a/graphs_trees/bst/dfs.py b/graphs_trees/bst/dfs.py new file mode 100644 index 0000000..021ed49 --- /dev/null +++ b/graphs_trees/bst/dfs.py @@ -0,0 +1,17 @@ +def in_order_traversal(node, visit_func): + if node is not None: + in_order_traversal(node.left, visit_func) + visit_func(node.data) + in_order_traversal(node.right, visit_func) + +def pre_order_traversal(node, visit_func): + if node is not None: + visit_func(node.data) + pre_order_traversal(node.left, visit_func) + pre_order_traversal(node.right, visit_func) + +def post_order_traversal(node, visit_func): + if node is not None: + post_order_traversal(node.left, visit_func) + post_order_traversal(node.right, visit_func) + visit_func(node.data) \ No newline at end of file diff --git a/graphs_trees/bst/test_bst.py b/graphs_trees/bst/test_bst.py index 894fc9e..fd37060 100644 --- a/graphs_trees/bst/test_bst.py +++ b/graphs_trees/bst/test_bst.py @@ -5,24 +5,24 @@ from nose.tools import assert_equal class TestTree(object): def test_tree(self): - root = Node(5) - root.insert(2) - root.insert(8) - root.insert(1) - root.insert(3) + node = Node(5) + insert(node, 2) + insert(node, 8) + insert(node, 1) + insert(node, 3) with captured_output() as (out, err): - root.in_order_traversal(sys.stdout.write) + in_order_traversal(node, sys.stdout.write) assert_equal(out.getvalue().strip(), '12358') - root = Node(1) - root.insert(2) - root.insert(3) - root.insert(4) - root.insert(5) + node = Node(1) + insert(node, 2) + insert(node, 3) + insert(node, 4) + insert(node, 5) with captured_output() as (out, err): - root.in_order_traversal(sys.stdout.write) + in_order_traversal(node, sys.stdout.write) assert_equal(out.getvalue().strip(), '12345') print('Success: test_tree')