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]. http://leetcode.com/onlinejudge#question_80

leetcode_remove_duplicates_from_sorted_arrsy_2.cpp

class Solution {
public:
    int removeDuplicates(int A[], int n) {
        int id = 0;
        int cur = 0;
        while (cur < n) {
            int cnt = 0;
            int val = A[cur];
            while (cur < n && val == A[cur]) {
                cur++;
                cnt++;
            }
            if (cnt == 1)
                A[id++] = val;
            else if (cnt >= 2) {
                A[id++] = val;
                A[id++] = val;
            }
        }
        return id;
    }
};