LeetCode 80 Remove Duplicates from Sorted Array II

LeetCode

80 Remove Duplicates from Sorted Array II

题目

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.

解答

class Solution {public:    int removeDuplicates(vector<int>& nums) {        const int n = nums.size();        if (n <= 2) return n;        int tail = 2;        for (int i = 2; i < n; i++)        {            if (nums[i] != nums[tail - 2])            nums[tail++] = nums[i];        }        return tail;    }};