/*

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(A==NULL||n<1) return 0;

int index = 1;

int count = 1; //当前这个数出现了几次

const int endCondition = 2; //表示数组最多可以出现endCondition个相同的数

for(int i=1;i<n;++i)

{

if(A[i]!=A[i-1]) //前后两个数不相等，直接复制过去

{

A[index++] = A[i];

count = 1;

}

else if((A[i]==A[i-1])&&(count<endCondition))//前后两个数相等，只有当前只出现一次的时候，才复制过去,

{

A[index++] = A[i];

count++;

}

}

return index;

}

};