From 8cc41e23afa4e7a458acfa5e2cf9c45cc905424e Mon Sep 17 00:00:00 2001
From: Donne Martin <donne.martin@gmail.com>
Date: Sun, 12 Jun 2016 23:25:49 -0400
Subject: [PATCH] Polish remove duplicates challenge and solution

Update constraints and algorithm discussion.
---
 .../remove_duplicates_challenge.ipynb         |  8 ++++---
 .../remove_duplicates_solution.ipynb          | 21 ++++++++-----------
 2 files changed, 14 insertions(+), 15 deletions(-)

diff --git a/linked_lists/remove_duplicates/remove_duplicates_challenge.ipynb b/linked_lists/remove_duplicates/remove_duplicates_challenge.ipynb
index 496ba8e..92a728f 100644
--- a/linked_lists/remove_duplicates/remove_duplicates_challenge.ipynb
+++ b/linked_lists/remove_duplicates/remove_duplicates_challenge.ipynb
@@ -38,9 +38,11 @@
     "    * Singly\n",
     "* Can you insert None values in the list?\n",
     "    * No\n",
-    "* Can you use additional data structures?\n",
-    "    * Implement both solutions\n",
     "* Can we assume we already have a linked list class that can be used for this problem?\n",
+    "    * Yes\n",
+    "* Can we use additional data structures?\n",
+    "    * Implement both solutions\n",
+    "* Can we assume this fits in memory?\n",
     "    * Yes"
    ]
   },
@@ -193,7 +195,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.4.3"
+   "version": "3.5.0"
   }
  },
  "nbformat": 4,
diff --git a/linked_lists/remove_duplicates/remove_duplicates_solution.ipynb b/linked_lists/remove_duplicates/remove_duplicates_solution.ipynb
index 74e5a89..ef1b974 100644
--- a/linked_lists/remove_duplicates/remove_duplicates_solution.ipynb
+++ b/linked_lists/remove_duplicates/remove_duplicates_solution.ipynb
@@ -38,9 +38,11 @@
     "    * Singly\n",
     "* Can you insert None values in the list?\n",
     "    * No\n",
-    "* Can you use additional data structures?\n",
-    "    * Implement both solutions\n",
     "* Can we assume we already have a linked list class that can be used for this problem?\n",
+    "    * Yes\n",
+    "* Can we use additional data structures?\n",
+    "    * Implement both solutions\n",
+    "* Can we assume this fits in memory?\n",
     "    * Yes"
    ]
   },
@@ -62,6 +64,8 @@
    "source": [
     "## Algorithm: Hash Map Lookup\n",
     "\n",
+    "Loop through each node\n",
+    "\n",
     "* For each node\n",
     "    * If the node's value is in the hash map\n",
     "        * Delete the node\n",
@@ -70,10 +74,7 @@
     "\n",
     "Complexity:\n",
     "* Time: O(n)\n",
-    "* Space: O(n)\n",
-    "\n",
-    "Note:\n",
-    "* Deletion requires two pointers, one to the previous node and one to the current node"
+    "* Space: O(n)"
    ]
   },
   {
@@ -84,17 +85,13 @@
     "\n",
     "* For each node\n",
     "    * Compare node with every other node\n",
-    "        * If the node's value is in the hash map\n",
-    "            * Delete the node\n",
-    "        * Else\n",
-    "            * Add node's value to the hash map\n",
+    "        * Delete nodes that match current node\n",
     "\n",
     "Complexity:\n",
     "* Time: O(n^2)\n",
     "* Space: O(1)\n",
     "\n",
     "Note:\n",
-    "* Deletion requires two pointers, one to the previous node and one to the current node\n",
     "* We'll need to use a 'runner' to check every other node and compare it to the current node"
    ]
   },
@@ -258,7 +255,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.4.3"
+   "version": "3.5.0"
   }
  },
  "nbformat": 4,