LeetCode (Remove Duplicates from Sorted Array II)

Problem:

Follow up for "Remove Duplicates":

What if duplicates are allowed at most twice?

For example,

Given sorted array nums = 

[1,1,1,2,2,3]

,

Your function should return length = 

5

, with the first five elements of nums being 

1

, 

1

, 

2

, 

2

 and 

3

.
It doesn't matter what you leave beyond the new length.
Solution:

class Solution {
public:
int removeDuplicates(vector<int>& nums) {
int n = 1, i = 1;
while(i < nums.size()){
if(nums[i] == nums[i - 1]){
n++;
if(n > 2){
nums.erase(nums.begin() + i);
n--;
}else i++;
}else{
n = 1;
i++;
}
}
return nums.size();
}
};