/* pre: Have list of available (Free) memory blocks, which could be empty.
* post: Uses a priority queue to sort the list in ascending order of memory block ID. */
public void sortFree()
{
PQueue sortQ = new PQueue();
for (Node cur = Free.getFirst(); cur != null; cur = cur.next())
sortQ.Enqueue(cur.value());
Free = new SinglyLinkedList();
while (sortQ.Count > 0)
Free.addLast(sortQ.Dequeue());
}
// 20 marks
/* pre: Have list of available memory blocks (Free) and list of memory blocks detected as being unusable (Corrupt),
* each of which could be empty. Each list is sorted in ascending order of memory block ID, with the first point of access
* having the smallest memory block ID value. Memory block IDs are unique within each list, but not necessarily unique
* across lists. Each memory block ID in the unusable list appears in the list of available memory blocks as well.
* post: In ascending order of memory block ID, display those available memory block IDs that are not corrupt.
* Determine and return the percentage (a value between 0 and 1) of the total size of the available memory blocks that
* are corrupt.
* NOTE: Each list may only be processed a MAXIMUM of 1 time.
* Make appropriate use of method getNextMemoryBlock (which must also be coded).
* The contents of the lists do not have to be retained. */
public double findWastage()
{
// ADD CODE FOR METHOD findWastage BELOW
sortFree(); //Change from descending to ascending so that smallest is first accessible
PQueue tempPQueue = new PQueue();
double totalCorrupt = 0;
int numberCorrupt = 0;
do
{
Block tempFree = getNextMemoryBlock(Free);
Block tempCorrupt = getNextMemoryBlock(Corrupt);
if (tempFree != null && tempCorrupt != null)
{
if (tempFree.MemID == tempCorrupt.MemID)
{
totalCorrupt += tempCorrupt.Size;
numberCorrupt++;
}
else
{
tempPQueue.Enqueue(tempFree);
tempPQueue.Enqueue(tempCorrupt);
}
}
else if (tempFree == null)
{
totalCorrupt += tempCorrupt.Size;
numberCorrupt++;
}
else
tempPQueue.Enqueue(tempFree);
}
while (Free.Count() > 0 || Corrupt.Count > 0);
int totalAvailable = 0;
while (tempPQueue.Count > 0)
{
Block tempBlock = (Block)tempPQueue.Dequeue();
tempBlock.display();
totalAvailable += tempBlock.Size;
}
Console.WriteLine("Total available memory = {0}kb",totalAvailable);
return numberCorrupt == 0 ? 0 : totalCorrupt / totalAvailable;
}
