0033.搜索旋转排序数组

https://leetcode.cn/problems/search-in-rotated-sorted-array/

方法一：二分搜索

时间复杂度 $O(\log n)$，空间复杂度 $O(1)$。

func search(nums []int, target int) int {
	left, right := 0, len(nums)-1
	for left <= right {
		mid := left + (right-left)/2
		if nums[mid] == target {
			return mid
		} else if nums[mid] >= nums[left] {
			if nums[left] <= target && nums[mid] > target {
				right = mid - 1
			} else {
				left = mid + 1
			}
		} else {
			if nums[mid] < target && nums[right] >= target {
				left = mid + 1
			} else {
				right = mid - 1
			}
		}
	}
	return -1
}