80. Remove Duplicates from Sorted Array II

class Solution 
{
public:
    int removeDuplicates(vector<int>& nums) 
    {
        int sz=nums.size();
        if(sz<3)
            return sz;
        int i=1,j=1,count=1; 
        while(j<sz)
        {
            if(nums[j]==nums[j-1])
            {
                count++;
                if(count>2)
                    j++;
                else
                    nums[i++]=nums[j++];
            }
            else
            {
                count=1;
                nums[i++]=nums[j++];
            }    
        }
        return i;
    }
};

双指针向前压缩，问题不大