From 79debf3d620c2fcd89ad33819d709209c88c16af Mon Sep 17 00:00:00 2001
From: Luke Else <mail@luke-else.co.uk>
Date: Thu, 10 Mar 2022 21:26:16 +0000
Subject: [PATCH] Updated bounds search on Doubly Linked List and completed
 traverse method

---
 C#/Datastructures/DoublyLinkedList.cs | 38 +++++++++++++++++++++++----
 C#/Program.cs                         | 26 ++++++++----------
 2 files changed, 44 insertions(+), 20 deletions(-)

diff --git a/C#/Datastructures/DoublyLinkedList.cs b/C#/Datastructures/DoublyLinkedList.cs
index 63d23a0..ffd668c 100644
--- a/C#/Datastructures/DoublyLinkedList.cs
+++ b/C#/Datastructures/DoublyLinkedList.cs
@@ -33,7 +33,7 @@ namespace C_.Datastructures
             get
             {
                 //Check Range
-                if (i >= Count) throw new System.Exception("Error! Index out of Bounds");
+                if (i >= Count || i < 0) throw new System.Exception("Error! Index out of Bounds");
 
                 //Return Value
                 DoublyLinkedListNode<T>? node = Traverse(i);
@@ -43,13 +43,28 @@ namespace C_.Datastructures
             set
             {
                 //Check Range
-                if (i >= Count) throw new System.Exception("Error! Index out of Bounds");
+                if (i >= Count || i < 0) throw new System.Exception("Error! Index out of Bounds");
 
                 //Change Value
                 DoublyLinkedListNode<T>? node = Traverse(i);
                 node!.Value = value;
             }
         }
+        public void Add(T value)
+        {
+            Count++;
+
+            if (Tail != null && Count > 0)
+            {
+                Tail.Next = new DoublyLinkedListNode<T> { Value = value, Next = null, Prev = Tail };
+                Tail = Tail.Next;
+                return;
+            }
+
+            Head = new DoublyLinkedListNode<T> { Value = value, Next = null, Prev = null };
+            Tail = Head;
+            
+        }
 
 
         private DoublyLinkedListNode<T>? Traverse()
@@ -66,17 +81,30 @@ namespace C_.Datastructures
 
             if (i > (Count/2))
             {
+                //reverse direction of search
                 direction = -1;
                 node = Tail;
-                i = Count - i;
+                //i becomes the amount of hops left to reach the item
+                i = Count - i - 1;
             }
 
             if (node != null)
             {
-                //continue to end of list
+
+
+
+                //continue to given point in the list ('i' hops)
                 for (int x = 0; x < i; x++)
                 {
-                    //Incomplete Traverse Functions
+                    if (direction == 1)
+                    {//Going forwards
+                        node = node!.Next;
+                    }
+                    else
+                    {
+                        node = node!.Prev;
+                    }
+
                 }
             }
             return node;
diff --git a/C#/Program.cs b/C#/Program.cs
index 76989c1..57d8941 100644
--- a/C#/Program.cs
+++ b/C#/Program.cs
@@ -5,22 +5,18 @@ using C_.Datastructures.Nodes;
 // See https://aka.ms/new-console-template for more information
 Console.WriteLine("Hello, World!");
 
-LinkedList<int> list = new();
+DoublyLinkedList<int> list = new DoublyLinkedList<int>();
 
-list.Append(1);
-list.Append(2);
-list.Append(3);
+list.Add(1);
+list.Add(2);
+list.Add(3);
+list.Add(4);
+list.Add(5);
+list.Add(6);
+list.Add(7);
+list.Add(8);
 
-LinkedList<int> list2 = new();
+var x = list[-6];
 
-list2.Append(1);
-list2.Append(2);
-list2.Append(3);
+Console.WriteLine(x);
 
-
-LinkedList<int> list3 = LinkedList<int>.Create(list, list2);
-
-list3.Insert(4, 1);
-list3.Delete(0);
-list3.Head = LinkedListNode<int>.Create(5, null);
-Console.ReadLine();
\ No newline at end of file