LeetCode Problem
540. Single Element in a Sorted Array
Link to LeetCode
You are given a sorted array consisting of only integers where every element appears exactly twice, except for one element which appears exactly once.
Return the single element that appears only once.
Your solution must run in O(log n) time and O(1) space.
Example 1:
Input: nums = [1,1,2,3,3,4,4,8,8]
Output: 2
Example 2:
Input: nums = [3,3,7,7,10,11,11]
Output: 10
logic: youtube solution
class Solution {
public int singleNonDuplicate(int[] nums) {
if (nums.length == 1) {
return nums[0];
}
int left = 0, right = nums.length-1;
while(left < right){
int mid = left + (right-left) / 2;
if( (mid % 2 == 0 && nums[mid] == nums[mid +1])
|| (mid %2 == 1 && nums[mid] == nums[mid - 1]) )
left = mid + 1;
else
right = mid;
}
return nums[left];
}
}