621. Task Scheduler

https://leetcode.com/problems/task-scheduler/

solution

class Solution:
    def leastInterval(self, tasks: List[str], n: int) -> int:
        count_dict = collections.defaultdict(int)
        for task in tasks:
            count_dict[task] += 1
        
        max_freq = max(count_dict.values())
        max_freq_count = 0
        for key, value in count_dict.items():
            if value == max_freq:
                max_freq_count += 1
        
        res = (max_freq - 1) * (n + 1) + max_freq_count
        return max(res, len(tasks))

时间复杂度：O(|tasks|) 空间复杂度：O(1)