LeetCode OJ：H-Index（H指数）

标签：

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.

感觉这题更加像动归，没写出来，看了别人的实现，代码如下：

 1 class Solution {
 2 public:
 3     int hIndex(vector<int>& citations) {
 4         int n = citations.size();
 5         vector<int>index(n + 1, 0);//注意这里是n+1
 6         for(int i = 0; i < n; ++i){
 7             if(citations[i]>=n)
 8                 index[n]++;
 9             else
10                 index[citations[i]]++;
11         }
12         if(index[n] >= n) return n;
13         for(int i = citations.size()-1; i >= 0; --i){
14             index[i]+=index[i+1];
15             if(index[i] >= i)
16                 return i;
17         }
18         return 0;
19     }
20 };

LeetCode OJ：H-Index（H指数）

标签：

原文地址：http://www.cnblogs.com/-wang-cheng/p/4992643.html