/*
* The array of tasks is given.
* Find the number of tasks that are performed simultaneusly.
*
* Complexety: O(n*log(n))
*/
public static List <Greedy_Task> FindOverlapNumber(Greedy_Task[] tasks)
{
List <Greedy_Task> overlapped = new List <Greedy_Task>();
if (tasks.Length <= 0)
{
return(overlapped);
}
if (tasks.Length == 1)
{
overlapped.Add(tasks[0]);
return(overlapped);
}
Greedy_Task[] starts = new Greedy_Task[tasks.Length];
for (int i = 0; i < tasks.Length; i++)
{
starts[i] = tasks[i];
}
Greedy_Task[] ends = new Greedy_Task[tasks.Length];
for (int i = 0; i < tasks.Length; i++)
{
ends[i] = tasks[i];
}
Array.Sort(starts, new Number_ComparerStarttime());
Array.Sort(ends, new Number_ComparerEndtime());
int startCoursor = 1;
int endCoursor = 0;
int currentNumber = 1;
int maxNumber = 1;
HashSet <Greedy_Task> tmpSet = new HashSet <Greedy_Task>();
tmpSet.Add(starts[0]);
while (startCoursor < tasks.Length && endCoursor < tasks.Length)
{
if (starts[startCoursor].Starttime < ends[endCoursor].Endtime)
{
currentNumber++;
tmpSet.Add(starts[startCoursor]);
if (currentNumber > maxNumber)
{
maxNumber = currentNumber;
overlapped.Clear();
foreach (Greedy_Task task in tmpSet)
{
overlapped.Add(task);
}
}
startCoursor++;
}
else
{
currentNumber--;
tmpSet.Remove(ends[endCoursor]);
endCoursor++;
}
}
return(overlapped);
}
public int CompareTo(object taskToCompare)
{
Greedy_Task task = taskToCompare as Greedy_Task;
return(this.endtime.CompareTo(task.Endtime));
}