Remove Duplicates from Sorted Array

EasyArraysTwo Pointers

Solve this the way you would in the interview: out loud, on a timer, with an AI interviewer asking follow-ups while you code. You get a scored report at the end.

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Problem

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. Consider the number of unique elements of nums to be k. To get accepted, you need to do the following: - Modify the array nums such that the first k elements of nums contain the unique elements in the order they were present in nums initially. - Return k.

Examples

Input: nums = [1,1,2]
Output: 2, nums = [1,2,_]
Your function should return k = 2, with the first two elements of nums being 1 and 2.
Input: nums = [0,0,1,1,1,2,2,3,3,4]
Output: 5, nums = [0,1,2,3,4,_,_,_,_,_]

Constraints

  • 1 <= nums.length <= 3 * 10^4
  • -100 <= nums[i] <= 100
  • nums is sorted in non-decreasing order.

What the interviewer grades

A correct solution is one of five scores. The report also grades problem understanding (did you clarify inputs and edge cases before coding), problem solving, communication while you work, code quality, and testing. See a sample report, or read up on the pattern in the lessons.

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