# LeetCode: Remove Duplicates from Sorted Array

https://leetcode.com/explore/featured/card/top-interview-questions-easy/92/array/727/

Given a sorted array nums, remove the duplicates in-place such that each element appear only once and return the new length.

Do not allocate extra space for another array, you must do this by modifying the input array in-place with O(1) extra memory.

Example 1:

Given nums = [1,1,2],

Your function should return length = 2, with the first two elements of nums being 1 and 2 respectively.

It doesn't matter what you leave beyond the returned length. Example 2:

Given nums = [0,0,1,1,1,2,2,3,3,4],

Your function should return length = 5, with the first five elements of nums being modified to 0, 1, 2, 3, and 4 respectively.

It doesn't matter what values are set beyond the returned length.

using Microsoft.VisualStudio.TestTools.UnitTesting;

namespace ArrayQuestions
{
/// <summary>
/// Remove Duplicates from Sorted Array
/// https://leetcode.com/explore/featured/card/top-interview-questions-easy/92/array/727/
/// </summary>
[TestClass]
public class RemoveDuplicatesfromSortedArray
{
[TestMethod]
public void RemoveDuplicates5()
{
int[] nums = {0, 0, 1, 1, 1, 2, 2, 3, 3, 4};
int[] excpected = {0, 1, 2, 3, 4};
int res = RemoveDuplicates(nums);
Assert.AreEqual(5,res);
for (int i = 0; i < res; i++)
{
Assert.AreEqual(excpected[i], nums[i]);
}
}

public int RemoveDuplicates(int[] nums)
{
if (nums.Length <= 1)
{
return nums.Length;
}

int current = nums[0];   //1
int newLength = 1;          //2
for (int i = 1; i < nums.Length; i++) // i = 5
{
if (nums[i] != current)
{
nums[newLength] = nums[i];  //0,1,2
newLength++;
current = nums[i];
}
//else continue to next item
}

return newLength;
}
}
}