public static void AllocateBlock(string ProcessName, int size, Block[] freeBlocks)
{
for (int i = 0; i < freeBlocks.Length; i++)
{
if (freeBlocks[i].isAvailable == true && freeBlocks[i].size >= size)
{
freeBlocks[i].isAvailable = false;
freeBlocks[i].processName = ProcessName;
break;
}
else if (freeBlocks[i].isAvailable == true && freeBlocks[i].size <= size)
{
//Traverse to allblocks till you get required space.
int nextAvailableIndexes = TraverseBuddy(size, i, freeBlocks);
if(nextAvailableIndexes !=0)
{
for (; i <= nextAvailableIndexes; i++)
{
freeBlocks[i].isAvailable = false;
freeBlocks[i].processName = ProcessName;
}
break;
}
}
}
}
public static void intializeMemory(Block[] freeBlocks,int size)
{
for (int i = 0; i < freeBlocks.Length; i++)
{
freeBlocks[i] = new Block();
freeBlocks[i].isAvailable = true;
freeBlocks[i].size = size;
freeBlocks[i].processName = "";
}
}
public static void DeAllocateBlock(string ProcessName, Block[] freeBlocks)
{
for (int i = 0; i < freeBlocks.Length; i++)
{
if (freeBlocks[i].processName == ProcessName)
{
freeBlocks[i].processName = "";
freeBlocks[i].isAvailable = true;
}
}
}
public static void MergeAndUnMergeBlocks(Block[] freeBlocks, List<Block> ActualBlocks)
{
ActualBlocks.Clear();
int memory = 0;
for (int i = 0; i < freeBlocks.Length; i++)
{
if (freeBlocks[i].isAvailable == false)
{
if (memory != 0)
{
Block freeBlock = new Block();
freeBlock.isAvailable = true;
freeBlock.processName = "";
freeBlock.size = memory;
ActualBlocks.Add(freeBlock);
memory = 0;
}
Block occupiedBlock = new Block();
occupiedBlock.isAvailable = false;
occupiedBlock.processName = freeBlocks[i].processName;
occupiedBlock.size = freeBlocks[i].size;
ActualBlocks.Add(occupiedBlock);
}
else
{
memory += freeBlocks[i].size;
}
}
if (memory != 0)
{
Block freeBlock = new Block();
freeBlock.isAvailable = true;
freeBlock.processName = "";
freeBlock.size = memory;
ActualBlocks.Add(freeBlock);
memory = 0;
}
}
static void Main(string[] args)
{
int maxLimit = 0;
int minLimit = 0;
while (true)
{
Console.WriteLine("Enter Max Limit");
string max = Console.ReadLine();
Console.WriteLine("Enter Min Limit");
string min = Console.ReadLine();
if (int.Parse(max) % int.Parse(min) == 0)
{
maxLimit = int.Parse(max);
minLimit = int.Parse(min);
break;
}
else
{
Console.WriteLine("Enter Again!.");
}
}
int sizeOfArray = maxLimit / minLimit;
Block[] freeBlocks = new Block[sizeOfArray];
intializeMemory(freeBlocks, minLimit);
List<Block> ActualBlocks = new List<Block>();
Block freeMemory = new Block();
freeMemory.isAvailable = true;
freeMemory.processName = "";
freeMemory.size = maxLimit;
ActualBlocks.Add(freeMemory);
Console.WriteLine("Intial State of Memory");
printMemory(ActualBlocks);
string fileName = "input.txt";
using (StreamReader sr = new StreamReader(fileName))
{
string line;
while ((line = sr.ReadLine()) != null)
{
string[] splittedlines = line.Split('\t');
int milliseconds = 2000;
Thread.Sleep(milliseconds);
if (splittedlines[0] == "E")
{
Console.WriteLine("Process " + splittedlines[1] + " Enter " + splittedlines[2] + "KB");
AllocateBlock(splittedlines[1], int.Parse(splittedlines[2]), freeBlocks);
MergeAndUnMergeBlocks(freeBlocks, ActualBlocks);
printMemory(ActualBlocks);
}
else
{
Console.WriteLine("Process " + splittedlines[1] + " Leave" );
DeAllocateBlock(splittedlines[1], freeBlocks);
MergeAndUnMergeBlocks(freeBlocks, ActualBlocks);
printMemory(ActualBlocks);
}
}
}
//Process A Enter
//Console.WriteLine("Process A Enter 7Kb");
//AllocateBlock("A", 7, freeBlocks);
//MergeAndUnMergeBlocks(freeBlocks, ActualBlocks);
//printMemory(ActualBlocks);
//Console.WriteLine("Process B Enter 3Kb");
//AllocateBlock("B", 3, freeBlocks);
//MergeAndUnMergeBlocks(freeBlocks, ActualBlocks);
//printMemory(ActualBlocks);
//Console.WriteLine("Process A Leaves 7Kb");
//DeAllocateBlock("A", freeBlocks);
//MergeAndUnMergeBlocks(freeBlocks, ActualBlocks);
//printMemory(ActualBlocks);
//Console.WriteLine("Process C Enter 6Kb");
//AllocateBlock("C", 6, freeBlocks);
//MergeAndUnMergeBlocks(freeBlocks, ActualBlocks);
//printMemory(ActualBlocks);
//Console.WriteLine("Process B Leaves 3Kb");
//DeAllocateBlock("B", freeBlocks);
//MergeAndUnMergeBlocks(freeBlocks, ActualBlocks);
//printMemory(ActualBlocks);
//Console.WriteLine("Process C Leaves 4Kb");
//DeAllocateBlock("C", freeBlocks);
//MergeAndUnMergeBlocks(freeBlocks, ActualBlocks);
//printMemory(ActualBlocks);
}
public static int TraverseBuddy(int size, int currentindex, Block[] freeBlocks)
{
int blockSize = 0;
for (int i = currentindex; i < freeBlocks.Length; i++)
{
if (freeBlocks[i].isAvailable == false)
{
return 0;
}
else
{
blockSize += freeBlocks[i].size;
if (blockSize >= size)
return i;
}
}
return 0;
}
