public MyFileList(string filename, MyFileList original)
{
length = original.length;
this.filename = filename;
if (File.Exists(filename))
{
File.Delete(filename);
}
try
{
using (BinaryWriter writer = new BinaryWriter(File.Open(filename,
FileMode.Create)))
{
writer.Write(4);
writer.Write(original.Head().Item1);
writer.Write(original.Head().Item2);
writer.Write(20);
for (int j = 1; j < length; j++)
{
original.Next();
writer.Write(original.CurrentData(original.currentNode).Item1);
writer.Write(original.CurrentData(original.currentNode).Item2);
writer.Write(original.nextNode);
}
}
this.fs = new FileStream(filename, FileMode.Open, FileAccess.ReadWrite);
}
catch (IOException ex)
{
Console.WriteLine(ex.ToString());
}
}
public void Replace(int index, MyFileList listas, int index2)
{
Byte[] data = new Byte[12];
listas.fs.Seek(index2 * 16 + 4, SeekOrigin.Begin);
listas.fs.Read(data, 0, 12);
fs.Seek(index * 16 + 4, SeekOrigin.Begin);
fs.Write(data, 0, 12);
}
public static void Test_File_List(int seed)
{
int n = 100;
string filename;
filename = @"myddatalist.dat";
MyFileList myFileList = new MyFileList(filename, n, seed);
myFileList.Print(n);
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
myFileList.mergeSort3Way();
stopwatch.Stop();
Console.WriteLine("sorted");
myFileList.Print(n);
Console.WriteLine("Number of data {0}", n);
Console.WriteLine("Time: {0}", stopwatch.Elapsed);
Console.WriteLine("Ticks: {0}", stopwatch.ElapsedTicks);
}
public static void mergeSort3WayRec(MyFileList gArray,
int low, int high, MyFileList destArray)
{
// If array size is 1 then do nothing
if (high - low < 2)
{
return;
}
// Splitting array into 3 parts
int mid1 = low + ((high - low) / 3);
int mid2 = low + 2 * ((high - low) / 3) + 1;
// Sorting 3 arrays recursively
mergeSort3WayRec(destArray, low, mid1, gArray);
mergeSort3WayRec(destArray, mid1, mid2, gArray);
mergeSort3WayRec(destArray, mid2, high, gArray);
// Merging the sorted arrays
merge(destArray, low, mid1, mid2, high, gArray);
}
// Function for 3-way merge sort process
public void mergeSort3Way()
{
// if array of size is zero returns null
if (this == null)
{
return;
}
GetReady();
// creating duplicate of given array
// copying elements of given array into
// duplicate array
MyFileList fArray = new MyFileList(@"mydatalistcopy.dat", this);
//// sort function
mergeSort3WayRec(fArray, 0, this.length, this);
//// copy back elements of duplicate array
//// to given array
for (int i = 0; i < fArray.Length; i++)
{
this.Replace(i, fArray, i);
}
fArray.fs.Close();
File.Delete(@"mydatalistcopy.dat");
}
/* Merge the sorted ranges [low, mid1), [mid1,
* mid2) and [mid2, high) mid1 is first midpoint
* index in overall range to merge mid2 is second
* midpoint index in overall range to merge*/
public static void merge(MyFileList gArray, int low,
int mid1, int mid2, int high,
MyFileList destArray)
{
int i = low, j = mid1, k = mid2, l = low;
// choose smaller of the smallest in the three ranges
while ((i < mid1) && (j < mid2) && (k < high))
{
if (gArray.Nodedata(i).CompareTo(gArray.Nodedata(j)) < 0)
{
if (gArray.Nodedata(i).CompareTo(gArray.Nodedata(k)) < 0)
{
destArray.Replace(l++, gArray, i++);
}
else
{
destArray.Replace(l++, gArray, k++);
}
}
else
{
if (gArray.Nodedata(j).CompareTo(gArray.Nodedata(k)) < 0)
{
destArray.Replace(l++, gArray, j++);
}
else
{
destArray.Replace(l++, gArray, k++);
}
}
}
// case where first and second ranges have
// remaining values
while ((i < mid1) && (j < mid2))
{
if (gArray.Nodedata(i).CompareTo(gArray.Nodedata(j)) < 0)
{
destArray.Replace(l++, gArray, i++);
}
else
{
destArray.Replace(l++, gArray, j++);
}
}
// case where second and third ranges have
// remaining values
while ((j < mid2) && (k < high))
{
if (gArray.Nodedata(j).CompareTo(gArray.Nodedata(k)) < 0)
{
destArray.Replace(l++, gArray, j++);
}
else
{
destArray.Replace(l++, gArray, k++);
}
}
// case where first and third ranges have
// remaining values
while ((i < mid1) && (k < high))
{
if (gArray.Nodedata(i).CompareTo(gArray.Nodedata(k)) < 0)
{
destArray.Replace(l++, gArray, i++);
}
else
{
destArray.Replace(l++, gArray, k++);
}
}
// copy remaining values from the first range
while (i < mid1)
{
destArray.Replace(l++, gArray, i++);
}
// copy remaining values from the second range
while (j < mid2)
{
destArray.Replace(l++, gArray, j++);
}
// copy remaining values from the third range
while (k < high)
{
destArray.Replace(l++, gArray, k++);
}
}
