274. H-Index

/* 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. 首先进行降序排序 寻找第一个第i个数小于i的位置，前一个位置的索引i即为H值。 */ #include <iostream> #include <vector> #include <algorithm> using namespace std; class Solution { public: static bool compares(int a,int b) { return a>b; } int hIndex(vector<int>& citations) { if(citations.empty()) return 0; sort(citations.begin(),citations.end(),Solution::compares); for(int j=0;j<citations.size();j++) cout<<citations[j]<<endl; int i=0; for(;i<citations.size();i++) { if(citations[i]<i+1) return i; } return i; } }; int main() { Solution mys; vector<int> citations={3,0,6,1,5}; cout<<mys.hIndex(citations)<<endl; return 0; }