Reverse Linked List II
Explore how to reverse nodes within a singly linked list between two given positions efficiently and in-place. This lesson helps you understand linked list manipulation techniques, ensuring you can solve such coding interview questions with effective memory usage and problem-solving clarity.
We'll cover the following...
Statement
Given a singly linked list with nodes and two positions, left and right, the objective is to reverse the nodes of the list from left to right. Return the modified list.
Constraints:
-
n -
node.value -
leftrightn
Examples
Understand the problem
Let’s take a moment to make sure you’ve correctly understood the problem. The quiz below helps you check if you’re solving the correct problem:
Reverse Linked List II
What is the output if the following linked list and left and right values are given as input?
linked list = 8 → 0 → 6 → 1 → 0 → 7 → 8 → 2
left = 1, right = 5
2 → 8 → 7 → 0 → 1 → 6 → 0 → 8
8 → 0 → 6 → 2 → 8 → 7 → 0 → 1
0 → 1 → 6 → 0 → 8 → 7 → 8 → 2
0 → 8 → 6 → 1 → 0 → 7 → 8 → 2
Figure it out!
We have a game for you to play. Rearrange the logical building blocks to develop a clearer understanding of how to solve this problem.
Try it yourself
Implement your solution in the following coding playground.
# Definition for a Linked List node# class ListNode:# def __init__(self, val=0, next=None):# self.val = val# self.next = nextfrom ds_v1.LinkedList.LinkedList import ListNodedef reverse_between(head, left, right):# Replace this placeholder return statement with your codereturn head