LeetCode 81. Search in Rotated Sorted Array II

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