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."
For example, given citations = [3, 0, 6, 1, 5], which 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, his h-index is 3.
Note: If there are several possible values for h, the maximum one is taken as the h-index.
Hint:
An easy approach is to sort the array first.What are the possible values of h-index?A faster approach is to use extra space.Credits:Special thanks to @jianchao.li.fighter for adding this problem and creating all test cases
1 public class Solution { 2 public int hIndex(int[] citations) { 3 if (citations == null || citations.length == 0) return 0; 4 Arrays.sort(citations); 5 int len = citations.length; 6 for (int i = 0; i < citations.length; i++) { 7 if (len <= citations[i]) 8 return len; 9 else 10 len--; 11 } 12 return len; 13 } 14 }
reference: https://leetcode.com/discuss/60791/simple-java-solution-with-sort
转载于:https://www.cnblogs.com/hygeia/p/4859946.html
