80. Remove Duplicates from Sorted Array II LeetCode Solution
In this guide, you will get 80. Remove Duplicates from Sorted Array II LeetCode Solution with the best time and space complexity. The solution to Remove Duplicates from Sorted Array II problem is provided in various programming languages like C++, Java, and Python. This will be helpful for you if you are preparing for placements, hackathons, interviews, or practice purposes. The solutions provided here are very easy to follow and include detailed explanations.
Problem Statement of 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.
Since it is impossible to change the length of the array in some languages, you must instead have the result be placed in the first part of the array nums. More formally, if there are k elements after removing the duplicates, then the first k elements of nums should hold the final result. It does not matter what you leave beyond the first k elements.
Return k after placing the final result in the first k slots of nums.
Do not allocate extra space for another array. You must do this by modifying the input array in-place with O(1) extra memory.
Custom Judge:
The judge will test your solution with the following code:
int[] nums = […]; // Input array
int[] expectedNums = […]; // The expected answer with correct length
int k = removeDuplicates(nums); // Calls your implementation
assert k == expectedNums.length;
for (int i = 0; i < k; i++) {
assert nums[i] == expectedNums[i];
}
If all assertions pass, then your solution will be accepted.
Example 1:
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).
Example 2:
Input: nums = [0,0,1,1,1,1,2,3,3]
Output: 7, nums = [0,0,1,1,2,3,3,_,_]
Explanation: Your function should return k = 7, with the first seven elements of nums being 0, 0, 1, 1, 2, 3 and 3 respectively.
It does not matter what you leave beyond the returned k (hence they are underscores).
Constraints:
1 <= nums.length <= 3 * 104
-104 <= nums[i] <= 104
nums is sorted in non-decreasing order.
Complexity Analysis
Time Complexity: O(n)
Space Complexity: O(1)
80. Remove Duplicates from Sorted Array II LeetCode Solution in C++
class Solution {
public:
int removeDuplicates(vector<int>& nums) {
int i = 0;
for (const int num : nums)
if (i < 2 || num > nums[i - 2])
nums[i++] = num;
return i;
}
}; /* code provided by PROGIEZ */
80. Remove Duplicates from Sorted Array II LeetCode Solution in Java
class Solution {
public int removeDuplicates(int[] nums) {
int i = 0;
for (final int num : nums)
if (i < 2 || num > nums[i - 2])
nums[i++] = num;
return i;
}
} // code provided by PROGIEZ
80. Remove Duplicates from Sorted Array II LeetCode Solution in Python
class Solution:
def removeDuplicates(self, nums: list[int]) -> int:
i = 0
for num in nums:
if i < 2 or num != nums[i - 2]:
nums[i] = num
i += 1
return i # code by PROGIEZ
