| package cn.edu.xidian.sselab.hashtable; /** * * @author zhiyong wang * title: H-Index * content: * 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. * */ public class HIndex { //这道题，自己理解错了题意，正确的理解方式是：论文被引用次数大于或者等于h次，这样的论文数量也要大于或者等于h，此时的h才是H //注：h的取值返回是[0,论文的总篇数] //首先是建立一个数组，用于将论文的引用次数从小到大进行排序，当然引用次数大于总论文个数的都放在数组的最后一位 //然后从数组最后一个开始，计算论文的个数是否大于或者等于论文引用的次数 public int hIndex(int[] citations){ int length = citations.length; int result = 0; if(length == 0) return 0; int[] index = new int[length+1]; for(int i=0;i<length;i++){ if(citations[i]>length){ index[length]++; }else{ index[citations[i]]++; } } for(int i=length;i>=0;i--){ if(result >= i) return i; result +=index[i]; } return 0; } } |