### LeetCode: Remove Duplicates from Sorted Array

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 System;

namespace Remove_Duplicates_from_Sorted_Array
{
class Program
{
static void Main(string[] args)
{

int[] arr = new int[] {0, 0, 1, 1, 1, 2, 2, 3, 3, 4};

var result = removeDuplicates(arr);

}

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

int i = 0;

for (int j = 1; j < nums.Length; j++)
{
if (nums[j] != nums[i])
{
i++;
nums[i] = nums[j];
}
}

return i + 1;
}
}
}


Complexity analysis

• Time complextiy : O(n). Assume that n is the length of array. Each of i and j traverses at most n steps.

• Space complexity : O(1)