H-index II--Leetcode

Given an array of citations (each citation was a non-negative integer) of a researcher, write a function to compute the RES Earcher ' s h-index.

According to the definition of H-index on Wikipedia: ' A scientist has index H if h of his/her N Papers has at least H citations each, and the other n−h papers has no more than H citation S each. "

For example, given citations = [3, 0, 6, 1, 5] , which means the researcher have papers in total and each of 5 them had received 3, 0, 6, 1, 5 Citatio NS respectively. Since the researcher have papers with at least citations each and the remaining both with 3 3 no more than 3 CIT Ations each, he h-index is 3 .

Note:if there was several possible values h for, the maximum one is taken as the h-index.

Follow up to H-index:what if the citations array is sorted in ascending order? Could you optimize your algorithm?

idea: Two-point search. Notice the boundary condition of the search.

1 classSolution {2  Public:3     intHindex (vector<int>&citations) {4         intleft =0, right = Citations.size ()-1;5          while(Left <=Right ) {6             intMid = left + (right-left)/2;7             if(Citations[mid] < citations.size ()-mid)8Left = mid +1;9             Else if(Mid > Left && citations[mid-1] >= citations.size ()-(Mid-1))Tenright = mid-1; One             Else returnCitations.size ()-mid; A         } -         return 0; -     } the};

H-index II--Leetcode