0621-task-scheduler.cs

publicclassSolution
{
privatePriorityQueue<FreqClass,int>pq;
privateDictionary<char,int>dictionary;
publicintLeastInterval(char[]tasks,intn)
{
// Count tasks in the array
if(n==0)
returntasks.Length;
dictionary=newDictionary<char,int>();
foreach(vartaskintasks)
{
if(dictionary.ContainsKey(task))
{
dictionary[task]++;
}
else
dictionary.Add(task,1);
}


pq=newPriorityQueue<FreqClass,int>(newMaxHeap());

vartime=0;

AddItemsToPQ();


while(pq.Count>0)
{
varlist=newList<FreqClass>();
varcnt=0;
for(vari=0;i<n+1;i++)
{
if(pq.Count>0)
{
varitem=pq.Dequeue();
cnt++;
//Console.WriteLine($"Dequeued {item.Task} with frequency : {item.Frequency}");
item.Frequency--;
if(item.Frequency>0)
list.Add(item);
}
}

for(vari=0;i<list.Count;i++)
{
varitem=list[i];
//Console.WriteLine($"Enqueued {item.Task} with frequency : {item.Frequency}");
pq.Enqueue(item,item.Frequency);
}

time+=pq.Count==0?cnt:n+1;
//Console.WriteLine($"Done with iteration, current time: {time}");
}

returntime;
}

privatevoidAddItemsToPQ()
{
foreach(varkeyValuePairindictionary)
{
pq.Enqueue(newFreqClass(keyValuePair.Value,0,keyValuePair.Key),keyValuePair.Value);
}
}

publicclassMaxHeap:IComparer<int>
{
publicintCompare(intx,inty)
{
returny-x;
}
}

publicclassFreqClass
{
publicintFrequency;
publicintIdleTime;
publiccharTask;

publicFreqClass(intfrequency,intidleTime,chartask)
{
Frequency=frequency;
IdleTime=idleTime;
Task=task;
}
}
}