Given an array of citations (each citation is a non-negative integer) of a researcher, write a function to compute the researcher's h-index.
According to the definition of h-index on Wikipedia: "A scientist has index h if h of his/her N papers have at least h citations each, and the other N − h papers have no more than h citations each."
Example:
Input:citations = [3,0,6,1,5]
Output: 3 Explanation:[3,0,6,1,5]
means the researcher has5
papers in total and each of them had received3, 0, 6, 1, 5
citations respectively. Since the researcher has3
papers with at least3
citations each and the remaining two with no more than3
citations each, her h-index is3
.
Note: If there are several possible values for h, the maximum one is taken as the h-index.
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class Solution:
def hIndex(self, citations: List[int]) -> int:
citations.sort()
size = len(citations)
# idx [0,size-1]
def f(idx):
nonlocal citations, size
return citations[idx] - (size - idx)
l, r, tgt = 0, size - 1, 0
while (l <= r):
mid = l + ((r - l) >> 1)
fm = f(mid)
if (tgt > fm):
l = mid + 1
else:
r = mid - 1
return size-l