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// @Title: 在排序数组中查找元素的第一个和最后一个位置 (Find First and Last Position of Element in Sorted Array)
// @Author: 15816537946@163.com
// @Date: 2020-12-23 23:08:49
// @Runtime: 4 ms
// @Memory: 3.9 MB
func searchRange(nums []int, target int) []int {
	if len(nums) == 0 {
		return []int{-1, -1}
	}
	first, last := -1, -1
	lo, hi := 0, len(nums)-1
	// 二分查找
	for lo <= hi {
		mid := (lo + hi) >> 1
		fmt.Println(mid)
		if nums[mid] == target {
			first, last = mid, mid
			break
		} else if nums[mid] > target {
			hi = mid - 1
		} else {
			lo = mid + 1
		}
	}

	if first != -1 {
		for first > 0 && nums[first] == nums[first-1] {
			first--
		}
		for last < len(nums)-1 && nums[last] == nums[last+1] {
			last++
		}
	}
	return []int{first, last}

}