/// <summary>
/// Фаза разделения, разделяем данный на два файла по сортированным фазам длинной step
/// </summary>
/// <param name="reader">Источник</param>
/// <param name="writerOne">Первый получатель</param>
/// <param name="writerTwo">Второй получатель</param>
/// <param name="step">Длина сортированной фазы</param>
private void Devision(StudentXmlReader reader, StudentXmlWriter writerOne, StudentXmlWriter writerTwo, long step)
{
while (reader.IsNext())
{
writerOne.Write(reader.Current);
for (long i = 1; (i < step) && reader.IsNext(); i++)
{
writerOne.Write(reader.Current);
}
for (long i = 0; (i < step) && reader.IsNext(); i++)
{
writerTwo.Write(reader.Current);
}
}
}
private void DoPhase(StudentXmlReader readerOne, StudentXmlReader readerTwo, StudentXmlWriter writer, long step)
{
var stepOne = step;
var stepTwo = step;
Student?currentFirst = null;
Student?currentSecond = null;
while (true)
{
currentFirst = ReadNextStudentInPhase(stepOne, readerOne, currentFirst);
currentSecond = ReadNextStudentInPhase(stepTwo, readerTwo, currentSecond);
if (!currentFirst.HasValue && !currentSecond.HasValue)
{
return;
}
if (!currentFirst.HasValue && currentSecond.HasValue)
{
FillRest(stepTwo, readerTwo, writer, currentSecond.Value);
return;
}
if (currentFirst.HasValue && !currentSecond.HasValue)
{
FillRest(stepOne, readerOne, writer, currentFirst.Value);
return;
}
if (currentFirst.Value.CompareTo(currentSecond.Value) > 0)
{
writer.Write(currentSecond.Value);
stepTwo--;
currentSecond = null;
}
else
{
writer.Write(currentFirst.Value);
stepOne--;
currentFirst = null;
}
}
}
private void FillRest(long step, StudentXmlReader reader, StudentXmlWriter writer, Student student)
{
var localStep = step;
Student?localStudent = student;
while (localStudent.HasValue)
{
writer.Write(localStudent.Value);
localStep--;
localStudent = ReadNextStudentInPhase(localStep, reader, null);
}
}