【LeetCode】081. Search in Rotated Sorted Array II

题目：

Follow up for "Search in Rotated Sorted Array":
What if duplicates are allowed?

Would this affect the run-time complexity? How and why?

Suppose an array sorted in ascending order is rotated at some pivot unknown to you beforehand.

(i.e., 0 1 2 4 5 6 7 might become 4 5 6 7 0 1 2).

Write a function to determine if a given target is in the array.

The array may contain duplicates.

题解：

Solution 1 

class Solution {
public:
    bool search(vector<int>& nums, int target) {
        int n = nums.size();
        int begin = 0, end = n;
        while(begin < end){
            int mid = begin + (end - begin) / 2;
            if(nums[mid] == target)
                return true;
            if(nums[begin] < nums[mid]){
                if(nums[begin] <= target && target < nums[mid])
                    end = mid;
                else
                    begin = mid + 1;
            } else if(nums[begin] > nums[mid]){
                if(nums[mid] < target && target <= nums[end - 1])
                    begin = mid + 1;
                else
                    end = mid;
            } else {
                ++begin;
            }
        }
        return false;
    }
};