[LeetCode] Remove Duplicates from Sorted Array II

Remove Duplicates from Sorted Array II

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.

解题思路：

这道题跟remove duplicates from sorted Array类似，就是比较的时候往前看2个即可，然后逐步移位。

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