You have a list of tasks to execute on a single processor. After completing a task, there is a mandatory cooldown period of k intervals before the same task can run again. During cooldown, the processor can run a different task or sit idle. Find the minimum number of intervals needed to execute all tasks.
For example, given tasks = ["A","A","A","B","B","B"] and k = 2, one optimal schedule is A B idle A B idle A B, requiring 8 intervals.
Explain your approach and state the time and space complexity.
How to approach it
- Hint 1
The task with the highest frequency determines the minimum schedule length.
- Hint 2
Imagine placing the most frequent task first with k-sized gaps between each occurrence. This creates a frame with idle slots that other tasks fill.
- Hint 3
The minimum intervals = max(total tasks, (maxFreq - 1) * (k + 1) + countOfTasksWithMaxFreq).
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