Task Scheduler

Medium

Given a string tasks of uppercase-letter task types and a cooldown n (passed as the second value), each task takes one unit and identical tasks must be at least n units apart. Return the minimum number of units to finish all tasks.

Example 1

Input:  tasks = "AAABBB", n = 2
Output: 8

Example 2

Input:  tasks = "AAABBB", n = 0
Output: 6

Constraints

• 1 <= tasks.length <= 10^4
• tasks are uppercase English letters.
• 0 <= n <= 100