# [LeetCode]#26. Remove Duplicates from Sorted Array

1 min readJul 25, 2024

**Environment: Python 3.8**

**Key technique: set, sorted**

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 1:**

`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).

Analysis

- Get set
- Sort it
- return result

Solution

`class Solution(object):`

def removeDuplicates(self, nums):

nums[:] = set(nums)

nums[:] =sorted(nums)

return len(nums)

**Submissions:**

Reference

https://leetcode.com/problems/remove-duplicates-from-sorted-array/submissions/1333492219/