g0001_0100.s0024_swap_nodes_in_pairs.readme.md Maven / Gradle / Ivy

Show more of this group Show more artifacts with this name
Show all versions of leetcode-in-kotlin Show documentation

Kotlin-based LeetCode algorithm problem solutions, regularly updated

There is a newer version: 1.28

24\. Swap Nodes in Pairs

Medium

Given a linked list, swap every two adjacent nodes and return its head. You must solve the problem without modifying the values in the list's nodes (i.e., only nodes themselves may be changed.)

**Example 1:**

![](https://assets.leetcode.com/uploads/2020/10/03/swap_ex1.jpg)

**Input:** head = [1,2,3,4]

**Output:** [2,1,4,3]

**Example 2:**

**Input:** head = []

**Output:** []

**Example 3:**

**Input:** head = [1]

**Output:** [1]

**Constraints:**

*   The number of nodes in the list is in the range `[0, 100]`.
*   `0 <= Node.val <= 100`