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.

 





 




 1 class Solution {
 2 public:
 3     int removeDuplicates(vector<int>& nums) {
 4         int len=nums.size();
 5         if(len<1)
 6         return 0;
 7         int end=0,flag=0;
 8         for(int i=1;i<len;i++)
 9         {
10             if(nums[i]==nums[end])
11             {
12                 if(flag==1)
13                 {
14                     
15                     continue;
16                 }
17                 flag=1;
18             }
19             else
20             flag=0;
21             end++;
22             if(i!=end)
23             nums[end]=nums[i];
24         }
25         return end+1;
26     }
27     
28 };