LeetCode/cpp/33.cpp at master · HONGJICAI/LeetCode · GitHub

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