274. H-Index

class Solution(object):
    def hIndex(self, citations):
        """
        :type citations: List[int]
        :rtype: int
        """
        citations.sort()
        n = len(citations)
        for i in xrange(n):
            if citations[i] >= (n-i):
                return n-i

        return 0

https://discuss.leetcode.com/topic/23810/python-o-n-lgn-time-with-sort-o-n-time-with-o-n-space