Is Split Linked List in Parts easy or hard?

Split Linked List in Parts is considered a medium difficulty problem. The main challenge is correctly distributing nodes across k parts while maintaining valid linked list structures and handling cases where the list has fewer nodes than k.

Split Linked List in Parts Python/Java solution

Python and Java implementations follow the same logic: compute the list length, determine the size of each part, and iterate through the list to detach segments. The algorithm uses simple pointer traversal and runs in O(n) time with constant extra memory.

How to solve Split Linked List in Parts in O(n)?

First traverse the linked list to count the number of nodes. Compute the base part size using n / k and determine how many parts need an extra node using n % k. Iterate through the list again, cutting the list after the required number of nodes for each part by setting the previous node's next pointer to null.

What is the best approach for Split Linked List in Parts?

The best approach calculates the total length of the linked list first, then determines the base size of each part using n / k and distributes the remaining nodes using n % k. After that, iterate through the list and detach each segment by adjusting next pointers. This runs in O(n) time and O(1) extra space.

Is Split Linked List in Parts asked at Google/Amazon/Meta?

Linked list partitioning and structural manipulation problems appear frequently in interviews at companies like Amazon, Google, and Meta. Variants of splitting or restructuring linked lists test pointer manipulation, traversal logic, and edge case handling.

What data structure is used in Split Linked List in Parts?

The problem uses a singly linked list. The solution focuses on pointer traversal, node counting, and modifying next references to break the list into independent segments.

What is the time complexity of Split Linked List in Parts?

The optimal solution runs in O(n) time where n is the number of nodes in the list. One pass computes the total length and another pass splits the list into k parts. The space complexity is O(1) excluding the output array of list heads.

Description Hints 1 Solution Video 11:01

725. Split Linked List in Parts

Medium70.6% acceptance5 companies

Given the head of a singly linked list and an integer k, split the linked list into k consecutive linked list parts.

The length of each part should be as equal as possible: no two parts should have a size differing by more than one. This may lead to some parts being null.

The parts should be in the order of occurrence in the input list, and parts occurring earlier should always have a size greater than or equal to parts occurring later.

Return an array of the k parts.

Example 1:

Input: head = [1,2,3], k = 5
Output: [[1],[2],[3],[],[]]
Explanation:
The first element output[0] has output[0].val = 1, output[0].next = null.
The last element output[4] is null, but its string representation as a ListNode is [].

Example 2:

Input: head = [1,2,3,4,5,6,7,8,9,10], k = 3
Output: [[1,2,3,4],[5,6,7],[8,9,10]]
Explanation:
The input has been split into consecutive parts with size difference at most 1, and earlier parts are a larger size than the later parts.

Constraints: