26. Remove Duplicates from Sorted Array - Easy

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. Then, return the number of unique elements in nums.

Consider the number of unique elements of nums to be k. To get accepted, you need to do the following things:

  • Change the array nums such that the first k elements of nums contain the unique elements in the order they were present in nums initially. The remaining elements of nums are not important as well as the size of nums.
  • Return k;
Example:
Input: nums = [1,1,2]

Output: 2, nums = [1,2,_]

Explanation:
Your function should return k = 2, with the first two elements of nums being 1 and 2, respectively. It does not matter what you leave beyond the returned k (hence, they are underscores).

Constraints:

  • 1 <= nums.length <= 3 * 10**4
  • -10**4 <= nums[i] <= 10**4
  • nums is sorted in non-decreasing order

Solution:
var removeDuplicates = function(nums) {

let k = 0;

for (let i = 0; i < nums.length; i++) {

    if (nums[i] !== nums[i+1) {

        nums[k] = nums[i];

        k++;

       }
   }

return k;

}


Thoughts:
I got the solution the first time!! Purely because of the LeetCode 27. Remove Element problem that I tackled just before. It is a very similar problem where all I have to do is compare the current index vs the next index and check if they are not the same. Then, update the nums array directly and return k. I'd give it a 9/10 purely because it's so similar and fresh in my brain to the previous question.

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