1647. Minimum Deletions to Make Character Frequencies Unique

https://leetcode.com/problems/minimum-deletions-to-make-character-frequencies-unique/

Python

from collections import Counter


class Solution:
    def minDeletions(self, s: str) -> int:
        counts = sorted(Counter(s).values(), reverse=True)

        ans = 0
        max_allowed = len(s)
        for count in counts:
            if count > max_allowed:
                ans += count - max_allowed
                max_allowed = max(0, max_allowed-1)
            else:
                max_allowed = max(0, count-1)
        return ans