Removing Duplicates from a integer list (Easy) | LeetCode Practice #7

Remove Duplicates From Sorted Array Given an integer array nums sorted in non-decreasing order, remove the duplicates in-place such that each unique element appears only once. The relative order of the elements should be kept the same. Consider the number of unique elements in nums to be k​​​​​​​​​​​​​​. After removing duplicates, return the number of unique elements k. The first k elements of nums should contain the unique numbers in sorted order. The remaining elements beyond index k - 1 can be ignored. Python ####Pop Elements(Runtime: 57ms, Memory: 13MB) #DECLARE nums: ARRAY of INTEGER class Solution(object): def removeDuplicates(self, nums): i = 1 while i < len(nums): if nums[i] == nums[i-1]: nums.pop(i) else: i += 1 return len(nums) ####Insert to Head(Runtime: 7ms, Memory: 13.7MB) #DECLARE nums: ARRAY of INTEGER class Solution(object): def removeDuplicates(self, nums): head_pointer = 1 for i in range(1, len(nums)): if nums[i] != nums[i-1]: nums[head_pointer] = nums[i] head_pointer += 1 return head_pointer Enter fullscreen mode Exit fullscreen mode Thoughts The question is simple. The only catch: we need to accept that the array can become messy, because after moving the unique elements to the front, anything after index k will be unorganized. However, since the question already states that "anything beyond index k-1 will not be considered", I think LeetCode is hinting at this approach.