Problem editorial

Insert Greatest Common Divisors in Linked List

MediumLinked List Manipulation PatternsLinked ListMathNumber Theory

Insert Greatest Common Divisors in Linked List: the approach in brief

The problem

You are given head, the first node of a singly linked list. Each node stores a positive integer, and the list is ordered from the head node toward the final node.

Pattern

Insert Greatest Common Divisors in Linked List is a Linked List Manipulation Patterns problem, in the Reordering / Partitioning subpattern. The pattern covers in-place reversal, merging sorted lists, reordering, and intersection detection

Approach outline

Walk through the list from left to right and inspect each node together with its successor.
The value inserted for a pair depends only on those two node values.
After inserting a node, continue from the next original node rather than processing the inserted node as part of another pair.

Complexity

The reference solution runs in O(n log V), where n is the number of original nodes and V is the maximum node value. time and O(n) for the inserted nodes, with O(1) auxiliary space. space.

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Practise Insert Greatest Common Divisors in Linked List and the problems around it

Insert Greatest Common Divisors in Linked List is a Linked List Manipulation Patterns problem, in the Reordering / Partitioning subpattern. Once the approach above makes sense, write it yourself and then work through the neighbouring problems that reuse it.

Insert Greatest Common Divisors in Linked List