Remove Duplicates from Sorted Array II

Follow up for "Remove Duplicates":
What if duplicates are allowed at most twice?

For example,
Given sorted array A = [1,1,1,2,2,3],

Your function should return length = 5, and A is now [1,1,2,2,3].

class Solution {
public:
    int removeDuplicates(int A[], int n) {
        if(n<=2) return n;
        int ans=2;
        for(int i=2;i<n;i++){
            if(A[ans-2]!=A[i])
             A[ans++]=A[i];
        }
        return ans;
    }
};