题目
题解
class Solution {
public:
int singleNonDuplicate(vector<int>& nums) {
int i = 0,j = nums.size() - 1;
int n = nums.size();
int mid;
while(i < j){
mid = i + (j - i)/2;
if(mid % 2 == 0){
if(mid + 1 < n && nums[mid] == nums[mid + 1])
i = mid + 1;
else
j = mid;
}
else{
if(mid - 1 >= 0 && nums[mid] == nums[mid - 1])
i = mid + 1;
else
j = mid;
}
}
return nums[i];
}
};