34. Find First and Last Position of Element in Sorted Array

We do a bisect left and bisect right to find the starting item in a sorted array, and then return both ranges.

class Solution:
    def searchRange(self, nums: List[int], target: int) -> List[int]:
        return [self.binary(nums, target, True), self.binary(nums, target, False)]
 
    def binary(self, nums, target, find_left):
        l, r = 0, len(nums) - 1
        ans = -1
        while l <= r:
            mid = (l + r) // 2
            if nums[mid] < target:
                l = mid + 1
            elif nums[mid] > target:
                r = mid - 1
            else:
                ans = mid
                if find_left:
                    r = mid - 1
                else:
                    l = mid + 1
        return ans