081. Search in Rotated Sorted Array II

 1 class Solution {
 2 public:
 3     bool search(vector<int>& nums, int target) {
 4         if (nums.size() == 0) return false;
 5         else {
 6             int first = 0, last = nums.size() - 1;
 7             while (first <= last) {
 8                 int mid = first + (last - first) / 2;
 9                 if (nums[mid] == target) return true;
10                 else {
11                     if (nums[first] < nums[mid]) {
12                         if (nums[first] <= target && target < nums[mid]) last = mid - 1;
13                         else first = mid + 1;
14                     }
15                     else if (nums[first] > nums[mid]) {
16                         if (nums[mid] < target && target <= nums[last]) first = mid + 1;
17                         else last = mid - 1;
18                     }
19                     else {
20                         ++first;
21                     }
22                 }
23             }
24             return false;
25         }
26     }
27 };