Single Element in a Sorted Array -- LeetCode 540

[Question]
Given a sorted array consisting of only integers where every element appears twice except for one element which appears 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.

[Solution]
//--- C++ ---
class Solution {
public:
    int singleNonDuplicate(vector<int>& nums) {
        int l=0, r=nums.size();
        int mid = 0;
        while (l+1<r) {
            mid = (l+r)>>1;
            if (nums[mid]==nums[mid^0x01])
                l = mid+1;
            else
                r = mid;
        }
        return nums[l];
    }
};

//--- Python ---
class Solution(object):
    def singleNonDuplicate(self, nums):
        lo, hi=0, len(nums)-1
        while lo<hi:
            m = (lo+hi)/2
            if nums[m]==nums[m^1]:
                lo = m+1
            else:
                hi = m
        return nums[lo]