You are given a list of tasks represented by characters and a cooldown period n. The same task must be separated by at least n intervals. Each interval is one unit of time, and the CPU can either execute a task or sit idle.
For example, given tasks = ["A","A","A","B","B","B"] and n = 2, one optimal schedule is A B idle A B idle A B, taking 8 intervals.
Explain your approach to finding the minimum number of intervals needed and state the time and space complexity.
How to approach it
- Hint 1
Think about which task constrains the schedule the most -- the one with the highest frequency.
- Hint 2
The most frequent task creates a frame of (maxFreq - 1) groups of size (n + 1), plus a final group for tasks with max frequency.
- Hint 3
The formula is: intervals = (maxFreq - 1) * (n + 1) + countOfMaxFreqTasks. But the answer is at least the total number of tasks.
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