#101 Remove Duplicates from Sorted Array II

题目描述：

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].

Have you met this question in a real interview? 

Yes

题目思路：

这题和#100基本上一样，就是增加了一个判断条件而已。

Mycode（AC = 43ms）：

class Solution {
public:
    /**
     * @param A: a list of integers
     * @return : return an integer
     */
    int removeDuplicates(vector<int> &nums) {
        // write your code here
        if (nums.size() <= 2) return nums.size();
        
        int idx = 1;
        for (int i = 2; i < nums.size(); i++) {
            if (nums[i] == nums[idx] && nums[i] == nums[idx - 1]) {
                continue;
            }
            else {
                nums[idx + 1] = nums[i];
                idx++;
            }
        }
        
        return idx + 1;
    }
};