Remove Duplicates From Sorted Array II Problem Solution

Remove Duplicates From Sorted Array II: Given an integer array nums sorted in non-decreasing order, remove some duplicates in-place such that each unique element appears at most twice. The relative order of the elements should be kept the same.

Example :

Input: nums = [1,1,1,2,2,3]
Output: 5, nums = [1,1,2,2,3,_]
Explanation: Your function should return k = 5, with the first five elements of nums being 1, 1, 2, 2 and 3 respectively.
It does not matter what you leave beyond the returned k (hence they are underscores).

Remove Duplicates From Sorted Array II Problem Solution

Problem Solution In Python

class Solution:
    def removeDuplicates(self, nums: List[int]) -> int:
        for num in nums:
            while nums.count(num) > 2:
                nums.remove(num)
         return len(nums)

Problem Solution In Java

public class Solution {
    public int removeDuplicates(int[] nums) {
        if(nums.length==0){
            return 0;
        }
        int x=1,index=0;
        for(int i=0;i<nums.length-1;i++){
            if(nums[i]==nums[i+1] && x==1){
                x++;
                nums[index++]=nums[i];
            }
            else if(nums[i]!=nums[i+1]){
                x=1;
                nums[index++]=nums[i];
            }
        }
        nums[index++]=nums[nums.length-1];
        return index;
    }
}

Problem Solution In C++

class Solution {
public:
    int removeDuplicates(vector<int>& nums) {
        if(nums.size()<3) return nums.size();
        int i =1;
        while (i<nums.size()){
            if(nums[i-1] == nums[i]){
                if(i == nums.size()-1) return nums.size();
                if(nums[i+1] == nums[i]) {nums.erase(nums.begin()+i);continue;}    
            }
            i++;
        }
        return nums.size();
    }
};

Problem Solution In C

int removeDuplicates(int* nums, int numsSize){
    if(!numsSize)
        return 0;
    int len = 0, count = 1;
    for (int i = 1; i < numsSize; i++)
    {
        if (nums[i] != nums[len])
        {
            len++;
            nums[len] = nums[i];
            count = 1;
        }
        else
        {
            count++;
            if (count <= 2)
            {
                len++;
                nums[len] = nums[i];
            }
        }
    }
    return len+1;
}