Schedule tasks with a cooldown so identical tasks are separated by at least n intervals, and compute the minimum total time needed.
You are given an array of tasks, where each task is represented by a capital letter, and an integer cooldown period n.
In one unit of time, you may either execute one task or stay idle. The same task type cannot be executed again until at least n other time units have passed since its last execution.
Return the minimum number of time units required to finish all tasks.
The goal is to arrange the task executions so that the cooldown constraint is satisfied while minimizing idle time.
Input Format
tasks: an array of task labels, typically uppercase letters.n: a non-negative integer cooldown interval.
Output Format
Return a single integer: the minimum number of time units needed to complete all tasks.
Constraints
1 <= tasks.lengthtasks[i]is a task label.0 <= n- The answer fits in a 32-bit signed integer.
Example 1
Input
tasks = ["A","A","A","B","B","B"], n = 2
Output
8
Explanation
One optimal schedule is A -> B -> idle -> A -> B -> idle -> A -> B, which takes 8 time units.
Example 2
Input
tasks = ["A","A","A","B","B","B"], n = 0
Output
6
Explanation
No cooldown is required, so the tasks can be executed back to back in any order.
Show 1 more example
Example 3
Input
tasks = ["A","A","A","B","B","B"], n = 1
Output
6
Explanation
One valid schedule is A -> B -> A -> B -> A -> B, which uses no idle time.
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