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Find First And Last Position of Element in Sorted Array

LeetCode has a Medium coding Problem in Its' Algorithm Section "Find First And Last Position of Element in Sorted Array". Today We are going to solve this problem.

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Question
Given an array of integers nums sorted in non-decreasing order, find the starting and ending position of a given target value.
If target is not found in the array, return [-1, -1].

You must write an algorithm with O(log n) runtime complexity.
Examples
Input: nums = [5,7,7,8,8,10], target = 8
Output: [3,4]
Input: nums = [5,7,7,8,8,10], target = 6
Output: [-1,-1]
Input: nums = [], target = 0
Output: [-1,-1]
Constraints to the problem:
0 <= nums.length <= 105
-109 <= nums[i] <= 109
nums is a non-decreasing array.
-109 <= target <= 109

Solution to Find First And Last Position of Element in Sorted Array
Skeleton Code given by Leetcode on its site.
class Solution(object):
def searchRange(self, nums, target):
"""
:type nums: List[int]
:type target: int
:rtype: List[int]
"""
To an ordered array of integers, find start and end positions of the same target, defines the time complexity is O (logn).

Solution: dichotomy, the complexity of the time typical binary search method, first using a binary search for the original array, find out the location of a target, and then find the start and end positions on both sides to search.
Complete Solution to the given problem
Visit https://hecodesit.com/find-first-and-last-position-of-element-in-sorted-array/ for solution

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