Task Scheduler

For the standard Task Scheduler problem, only task frequencies and cooldown n matter. Let maxFreq be the largest frequency and maxCount the number of task types with that frequency. Arrange one maximum-frequency task into maxFreq-1 blocks separated by cooldown slots. The minimum schedule length is max(tasks.length, (maxFreq-1)*(n+1)+maxCount). The second term accounts for the final tasks that close the last block; the first handles cases where other tasks fill every idle slot. This is O(T) time and O(1) space for a fixed alphabet, or O(T) map space generally. An alternative simulation uses a max-heap plus cooldown queue, useful when the actual schedule is requested. Test n=0, one task type, and multiple equally frequent tasks. Do not insert idle time merely because a cooldown exists; plentiful other tasks may eliminate it.