public int CompareTo(object obj)
{
if (obj == null)
{
return(1);
}
CharacterFrequency cf = obj as CharacterFrequency;
if (obj != null)
{
int result = 0;
if (this.m_count > cf.m_count)
{
result = -1;
}
else if (this.m_count == cf.m_count)
{
result = 0;
}
else
{
result = 1;
}
return(result);
}
else
{
throw new ArgumentException("object is not a Character Frequency");
}
}
public override bool Equals(object obj)
{
if (obj == null)
{
return(false);
}
if (obj == this)
{
return(true);
}
if (!(obj.GetType() == GetType()))
{
return(false);
}
bool equal = false;
CharacterFrequency cf = new CharacterFrequency('\0', 0);
cf = (CharacterFrequency)obj;
if (this.character == cf.character)
{
equal = true;
}
return(equal);
}
static LinkedList <CharacterFrequency> Charactercounting(String Filepath, LinkedList <CharacterFrequency> cflist)
{
StreamReader sr = new StreamReader(Filepath);
int text = 0;
text = sr.Read();
if (text == -1)
{
sr.Close();
return(cflist);
}
else
{
//Reading the File
while (text != -1)
{
CharacterFrequency cf = new CharacterFrequency((char)text, 1);
LinkedListNode <CharacterFrequency> node = cflist.Find(cf);
if (node != null)
{
node.Value.increment();
}
else
{
cflist.AddFirst(cf);
}
text = sr.Read();
}
sr.Close();
//Ordering the Linked List
CharacterFrequency[] cfa = cflist.ToArray();
Array.Sort(cfa);
cflist.Clear();
for (int i = 0; i < cfa.Length; i++)
{
cflist.AddFirst(cfa[i]);
}
//Debugging
//LinkedListNode<CharacterFrequency> snode = cflist.First;
//while (snode != null)
//{
// Console.WriteLine(snode.Value.ToString());
// snode = snode.Next;
//}
//End of debugging
return(cflist);
}
}
static LinkedList <BinaryTree <CharacterFrequency> > buildTree(LinkedList <CharacterFrequency> cflist, LinkedList <BinaryTree <CharacterFrequency> > tree)
{
LinkedListNode <CharacterFrequency> node = cflist.First;
//Turn all the CharacterFrequency's into BinaryTree roots and add them to a LinkedList of Binarytrees of Characterfrequencys
while (node != null)
{
BinaryTree <CharacterFrequency> bt = new BinaryTree <CharacterFrequency>();
bt.Insert(node.Value, BinaryTree <CharacterFrequency> .Relative.root);
tree.AddLast(bt);
node = node.Next;
}
BinaryTree <CharacterFrequency> bt1 = new BinaryTree <CharacterFrequency>();
BinaryTree <CharacterFrequency> bt2 = new BinaryTree <CharacterFrequency>();
//Creating the Binary Tree
while (tree.Count > 1)
{
//Remove first two elements
bt1 = tree.First();
tree.RemoveFirst();
bt2 = tree.First();
tree.RemoveFirst();
//Sums the two elements and creates a new node
int sum = bt1.Current.Data.count + bt2.Current.Data.count;
CharacterFrequency cf = new CharacterFrequency('\0', sum);
BinaryTree <CharacterFrequency> ptrBT_new = new BinaryTree <CharacterFrequency>();
ptrBT_new.Insert(cf, BinaryTree <CharacterFrequency> .Relative.root);
ptrBT_new.Insert(bt1.Root, BinaryTree <CharacterFrequency> .Relative.leftChild);
ptrBT_new.Insert(bt2.Root, BinaryTree <CharacterFrequency> .Relative.rightChild);
//Adds the Root into the list ordered by count from smallest to largest
if (tree.Count == 0)
{
tree.AddFirst(ptrBT_new);
}
else if (tree.First.Value.Root.Data.count >= ptrBT_new.Root.Data.count)
{
tree.AddFirst(ptrBT_new);
}
else if (tree.Last.Value.Root.Data.count <= ptrBT_new.Root.Data.count)
{
tree.AddLast(ptrBT_new);
}
else
{
LinkedListNode <BinaryTree <CharacterFrequency> > treenode = tree.First;
while (treenode.Value.Root.Data.count < ptrBT_new.Root.Data.count && treenode != null)
{
treenode = treenode.Next;
}
tree.AddBefore(treenode, ptrBT_new);
}
//clean up
cf = null;
ptrBT_new = null;
bt1 = null;
bt2 = null;
}
return(tree);
}
static void Main(string[] args)
{
Console.WriteLine("To compress a file enter Compress, to decompress a file enter Decompress\tTo exit type Exit");
String enter = Console.ReadLine();
String filePath = null;
while (enter.ToLower() != "exit")
{
//****************Compression******************//
if (enter.ToLower() == "compress")
{
Console.WriteLine("Please enter in the absolute path for the file:");
filePath = Console.ReadLine();
try
{
LinkedList <CharacterFrequency> cflist = new LinkedList <CharacterFrequency>();
Console.WriteLine("Counting characters please wait!");
Charactercounting(filePath, cflist);
Console.WriteLine("Characters Counted!");
//Check to see if the file is empty
if (cflist.Count == 0)
{
Console.WriteLine("Cannot compress a file that is empty. Please re enter another command");
enter = Console.ReadLine();
}
else
{
//Variables created only if we're comrpessing and the file isnt empty.
String newFile = null;
String addName = "_Encode.txt";
LinkedList <encoding> encode = new LinkedList <encoding>();
LinkedList <BinaryTree <CharacterFrequency> > tree = new LinkedList <BinaryTree <CharacterFrequency> >();
//Write the cflist onto the encoding file here
newFile = getNewFileName(filePath, addName);
if (File.Exists(newFile))
{
File.Delete(newFile);
}
File.Create(newFile).Close();
StreamWriter sw = new StreamWriter(newFile, false);
LinkedListNode <CharacterFrequency> node = cflist.First;
sw.WriteLine(cflist.Count + "\n");
while (node != null)
{
sw.WriteLine(node.Value.Print());
node = node.Next;
}
sw.Close();
String newfileText = getNewFileName(filePath, "_EncodeText.txt");
//Building tree
Console.WriteLine("Building tree, please wait");
buildTree(cflist, tree);
Console.WriteLine("Tree built!");
encodeTable(tree, encode);
//compression
Console.WriteLine("Compressing File please do NOT exit the program");
StreamReader sr = new StreamReader(filePath);
compress(encode, newfileText, sr);
sr.Close();
Console.WriteLine("File encoded!");
Console.WriteLine("Please enter another command");
enter = Console.ReadLine();
}
}
catch (Exception e)
{
Console.WriteLine(e.Message);
Console.WriteLine("The file could not be opened, make sure you gave the right path to the file.");
Console.WriteLine("Please re enter another command");
enter = Console.ReadLine();
}
}
//************Decompression***************//
else if (enter.ToLower() == "decompress")
{
Console.WriteLine("Please enter the absolute path of the file that you want to decompress");
filePath = Console.ReadLine();
try
{
String encodeFile;
encodeFile = getNewFileName(filePath, "_Encode.txt");
String encodeText = getNewFileName(filePath, "_EncodeText.bin");
String decompressPath = getNewFileName(filePath, "_Decode.txt");
if (File.Exists(encodeFile) && File.Exists(encodeText))
{
//Variables
StreamReader sr = new StreamReader(encodeFile);
LinkedList <CharacterFrequency> cflist = new LinkedList <CharacterFrequency>();
//get the total number of unique characters in the file so it knows when to stop;
int listcount = int.Parse(sr.ReadLine());
int counter = 0;
sr.ReadLine();
//gets the total number of characters in the file
//Creating the Tree
String line = sr.ReadLine();
Char[] split = new Char[] { ',' };
String[] results;
//Recreating the Linked List of CharacterFrequencys
while (counter < listcount)
{
results = line.Split(split, StringSplitOptions.None);
CharacterFrequency cf = new CharacterFrequency(int.Parse(results[0]), int.Parse(results[1]));
cflist.AddLast(cf);
sr.ReadLine();
line = sr.ReadLine();
counter++;
}
sr.Close();
//gets the total
int totalchar = total(cflist);
LinkedList <BinaryTree <CharacterFrequency> > tree = new LinkedList <BinaryTree <CharacterFrequency> >();
Console.WriteLine("Building tree, please wait");
buildTree(cflist, tree);
Console.WriteLine("Tree built");
//Decompressing
Console.WriteLine("Decompressing File please do NOT exit the program");
decompress(tree, encodeText, decompressPath, totalchar);
Console.WriteLine("File Decompressed!");
Console.WriteLine("Please enter another command");
enter = Console.ReadLine();
}
else
{
Console.WriteLine("Cannot decompress a file when the encoding table could not be found");
Console.WriteLine("Either the encoding table was lost or the file you selected was not compressed");
Console.WriteLine("Please enter another command");
enter = Console.ReadLine();
}
}
catch (Exception e)
{
Console.WriteLine(e.Message);
Console.WriteLine("The file could not be opened, make sure that you gave the right path to the file.");
Console.WriteLine("Please re enter another command");
enter = Console.ReadLine();
}
}
else
{
Console.WriteLine("Please enter in a valid command");
enter = Console.ReadLine();
}
}
Environment.Exit(0);
}
static void Main(string[] args)
{
Console.WriteLine(" To decompress a file enter a method of input 'FILE/MANUAL'");
String enter = Console.ReadLine();
String filePath = null;
if (enter.ToLower() == "file")
{
//Reading from file
Console.WriteLine("Please enter the absolute path of the file that you want to decompress");
filePath = Console.ReadLine();
try
{
String encodeFile;
encodeFile = getNewFileName(filePath, "_Encode.txt");
String encodeText = getNewFileName(filePath, "_EncodeText.bin");
String decompressPath = getNewFileName(filePath, "_Decode.txt");
if (File.Exists(encodeFile) && File.Exists(encodeText))
{
//Variables
StreamReader sr = new StreamReader(encodeFile);
LinkedList <CharacterFrequency> cflist = new LinkedList <CharacterFrequency>();
//get the total number of unique characters in the file so it knows when to stop;
int listcount = int.Parse(sr.ReadLine());
int counter = 0;
sr.ReadLine();
//gets the total number of characters in the file
//Creating the Tree
String line = sr.ReadLine();
Char[] split = new Char[] { ',' };
String[] results;
//Recreating the Linked List of CharacterFrequencys
while (counter < listcount)
{
results = line.Split(split, StringSplitOptions.None);
CharacterFrequency cf = new CharacterFrequency(int.Parse(results[0]), int.Parse(results[1]));
cflist.AddLast(cf);
sr.ReadLine();
line = sr.ReadLine();
counter++;
}
sr.Close();
//gets the total
int totalchar = total(cflist);
LinkedList <BinaryTree <CharacterFrequency> > tree = new LinkedList <BinaryTree <CharacterFrequency> >();
Console.WriteLine("Building tree, please wait");
buildTree(cflist, tree);
Console.WriteLine("Tree built");
//Decompressing
Console.WriteLine("Decompressing File please do NOT exit the program");
decompressFile(tree, encodeText, decompressPath, totalchar);
Console.WriteLine("File Decompressed!");
Console.WriteLine("Please enter another command");
enter = Console.ReadLine();
}
else
{
Console.WriteLine("Cannot decompress a file when the encoding table could not be found");
Console.WriteLine("Either the encoding table was lost or the file you selected was not compressed");
Console.WriteLine("Please enter another command");
enter = Console.ReadLine();
}
}
catch (Exception e)
{
Console.WriteLine(e.Message);
Console.WriteLine("The file could not be opened, make sure that you gave the right path to the file.");
Console.WriteLine("Please re enter another command");
enter = Console.ReadLine();
}
}
else if (enter.ToLower() == "manual")
{
String decompressPath = getNewFileName(filePath, "_Decode.txt");
Console.WriteLine(" Input characters, to exit write 'exit'");
Console.WriteLine(" Input must be in a form of 'X,3'");
LinkedList <CharacterFrequency> cflist = new LinkedList <CharacterFrequency>();
while (true)
{
String input = Console.ReadLine();
if (input.ToLower() != "exit")
{
break;
}
Char[] split = new Char[] { ',' };
String[] results;
results = input.Split(split, StringSplitOptions.None);
CharacterFrequency cf = new CharacterFrequency(int.Parse(results[0]), int.Parse(results[1]));
cflist.AddLast(cf);
}
//Recreating the Linked List of CharacterFrequen
int totalchar = total(cflist);
LinkedList <BinaryTree <CharacterFrequency> > tree = new LinkedList <BinaryTree <CharacterFrequency> >();
Console.WriteLine("Building tree, please wait");
buildTree(cflist, tree);
Console.WriteLine("Tree built");
//Decompressing
Console.WriteLine("Decompressing File please do NOT exit the program");
decompressManual(tree, decompressPath, totalchar);
Console.WriteLine("File Decompressed!");
Console.WriteLine("Please enter another command");
enter = Console.ReadLine();
}
}