0274-h-index¶
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Description¶
Given an array of integers citations where citations[i] is the number of citations a researcher received for their ith paper, return the researcher's h-index.
According to the definition of h-index on Wikipedia: The h-index is defined as the maximum value of h such that the given researcher has published at least h papers that have each been cited at least h times.
Example 1:
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.
Example 2:
Input: citations = [1,3,1] Output: 1
Constraints:
n == citations.length1 <= n <= 50000 <= citations[i] <= 1000
Solution(Python)¶
class Solution:
def hIndex(self, citations: List[int]) -> int:
# citations = [3,0 6,1,5]
# h number of papers <= h
# range : 0...n
# h= 1
# 0 1 3 5 6
# no
# h =2
# 3 <= 2 false
# h =3
# 3<=3 True
# sorted find the partition where h >= number of parers form right
#
# 3 0 6 1 5
# after sorting: 6 5 3 1 0
# h h +1 citaitions condition res
# 0 1 6 6>= 1 1
# 1 2 5 5>=1 2
# 2 3 3 3>=1 3
# 4 5 1 2>=5 3
# 5 6 0 1>=6 3
#
# 1 1 1 1 1
# 0 1 1 1>=1 1
# 1 2 1 1>=2 1
# 2 3 1
n = len(citations)
if n == 0:
return 0
citations.sort(reverse=True)
res = 0
for h in range( n):
if citations[h] >= h + 1 :
res = h + 1
else:
return res
return res