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{
"cells": [
{
"cell_type": "markdown",
"metadata": {},
"source": [
"# May June 2017 Question 4\n",
"> As homework due for March 04, 2025"
]
},
{
"cell_type": "code",
"execution_count": 1,
"metadata": {},
"outputs": [],
"source": [
"# Q4b\n",
"class Node:\n",
" def __init__(self, data, pointer):\n",
" self.__Data = data\n",
" self.__Pointer = pointer\n",
" def CreateNode(data, pointer):\n",
" pass\n",
" def SetData(data):\n",
" self.__Data = data\n",
" def SetPointer(pointer):\n",
" self.__Pointer = pointer\n",
" def GetData():\n",
" return self.__Data\n",
" def GetPointer():\n",
" return self.__Pointer\n",
" ### DEBUG FN\n",
" def __str__(self):\n",
" return f\"[{self.__Data}] -> ({self.__Pointer})\""
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Q4 c)\n",
"- i. A null pointer is a pointer that does not point to anything, indicating the end of a list.\n",
"- ii. Value: -1; -1 is one less than the smallest index that can occur in the array, so it can be used to index a non-existent element."
]
},
{
"cell_type": "code",
"execution_count": 2,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"[None, None, None, None, None, None, None, None]\n",
"at: 0\n",
"at: 1\n",
"at: 2\n",
"at: 3\n",
"at: 4\n",
"at: 5\n",
"at: 6\n",
"[0] [None] -> (1)\n",
"[1] [None] -> (2)\n",
"[2] [None] -> (3)\n",
"[3] [None] -> (4)\n",
"[4] [None] -> (5)\n",
"[5] [None] -> (6)\n",
"[6] [None] -> (7)\n",
"[7] [None] -> (-1)\n"
]
}
],
"source": [
"# Q4 c) iii)\n",
"NULL_POINTER = -1\n",
"NODE_ARRAY_LENGTH = 8\n",
"class LinkedList:\n",
" def __init__(self):\n",
" self.__HeadPointer = -1\n",
" self.__FreePointer = 0\n",
" node_arr = [None for i in range(NODE_ARRAY_LENGTH)]\n",
" print(node_arr)\n",
" for i in range(len(node_arr) - 1):\n",
" print(f\"at: {i}\")\n",
" node_arr[i] = Node(None, i+1)\n",
" node_arr[len(node_arr) - 1] = Node(None, NULL_POINTER)\n",
" self.__NodeArray = node_arr\n",
" ## DEBUG FN\n",
" def printme(self):\n",
" i = 0\n",
" for elem in self.__NodeArray:\n",
" print(f\"[{i}] {elem}\")\n",
" i += 1\n",
"## DEBUG CODE\n",
"l = LinkedList()\n",
"l.printme()"
]
},
{
"cell_type": "code",
"execution_count": 3,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"[None, None, None, None, None, None, None, None]\n",
"at: 0\n",
"at: 1\n",
"at: 2\n",
"at: 3\n",
"at: 4\n",
"at: 5\n",
"at: 6\n"
]
}
],
"source": [
"# Q4 c) iv)\n",
"contacts = LinkedList()"
]
},
{
"cell_type": "code",
"execution_count": 4,
"metadata": {},
"outputs": [],
"source": [
"# ... from Q4 c) iii) ...\n",
"def OutputListToConsole(self):\n",
" i = 0\n",
" for elem in self.__NodeArray:\n",
" print(f\"[{i}] {elem}\")\n",
" i += 1"
]
}
],
"metadata": {
"kernelspec": {
"display_name": ".venv",
"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": "3.12.7"
}
},
"nbformat": 4,
"nbformat_minor": 2
}
|
