The Fellow Programmer

Given an array of citations sorted in ascending order (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." Example: Input: citations = [0,1,3,5,6] Output: 3 Explanation: [0,1,3,5,6] means the researcher has 5 papers in total and each of them had received 0 , 1, 3, 5, 6 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, her h-index is 3 . Note: If there are several possible values for  h , the maximum one is taken as the h-index.   class Solution {     public int hIndex(int[] citations) {         int length = citations.length;    

You are given a sorted array consisting of only integers where every element appears exactly twice, except for one element which appears exactly once. Find this single element that appears only once. Example 1: Input: [1,1,2,3,3,4,4,8,8] Output: 2 Example 2: Input: [3,3,7,7,10,11,11] Output: 10 Note: Your solution should run in O(log n) time and O(1) space. METHOD 1:   class Solution {     public int singleNonDuplicate(int[] nums) {         int result = 0;         for(int num:nums)             result ^= num;         return result;     } } Try it on Leetcode Here we are going to do XOR operation. Because, in the problem itself they mentioned that each number in array repeated twice and only one number occurs once. Also XOR of same number is 0 and if continue doing with all numbers the final result contains that non repeating number. Time Complexity: O(N) But in the question note, they mention that we have to finish the iteration in O(logN). Th