Leetcode daily question solution: 540 A single element in an ordered array

Give you an ordered array of integers only , Each of these elements will appear twice , Only one number will appear once .

Please find and return the number that only appears once .

The solution you design must meet O(log n) Time complexity and O(1) Spatial complexity .

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

Their thinking ： Try it first Counter Function calculation array nums The number of occurrences of each element in , Then find the output that appears once

Code ：

class Solution:
    def singleNonDuplicate(self, nums: List[int]) -> int:
        return [i for i,j in Counter(nums).items() if j==1 ][0]