H-Index Python Solution with Tests

lcpy gen -n 274   # by problem number
lcpy gen -s h_index   # by problem name

Input: citations = [3,0,6,1,5]
Output: 3
Explanation: [3,0,6,1,5] means the researcher has 5 papers in total and each of them had received 3, 0, 6, 1, 5 citations respectively. Since the researcher has 3 papers with at least 3 citations each and the remaining two with no more than 3 citations each, their h-index is 3.

Input: citations = [1,3,1]
Output: 1

class Solution:
    # Time: O(n)
    # Space: O(n)
    def h_index(self, citations: list[int]) -> int:
        n = len(citations)
        buckets = [0] * (n + 1)
        for c in citations:
            buckets[min(c, n)] += 1
        total = 0
        for h in range(n, -1, -1):
            total += buckets[h]
            if total >= h:
                return h
        return 0