{ "data": { "question": { "questionId": "23", "questionFrontendId": "23", "boundTopicId": null, "title": "Merge k Sorted Lists", "titleSlug": "merge-k-sorted-lists", "content": "

You are given an array of k linked-lists lists, each linked-list is sorted in ascending order.

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Merge all the linked-lists into one sorted linked-list and return it.

\n\n

 

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Example 1:

\n\n
\nInput: lists = [[1,4,5],[1,3,4],[2,6]]\nOutput: [1,1,2,3,4,4,5,6]\nExplanation: The linked-lists are:\n[\n  1->4->5,\n  1->3->4,\n  2->6\n]\nmerging them into one sorted list:\n1->1->2->3->4->4->5->6\n
\n\n

Example 2:

\n\n
\nInput: lists = []\nOutput: []\n
\n\n

Example 3:

\n\n
\nInput: lists = [[]]\nOutput: []\n
\n\n

 

\n

Constraints:

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0 : val)\n * this.next = (next===undefined ? null : next)\n * }\n */\n/**\n * @param {ListNode[]} lists\n * @return {ListNode}\n */\nvar mergeKLists = function(lists) {\n \n};", "__typename": "CodeSnippetNode" }, { "lang": "TypeScript", "langSlug": "typescript", "code": "/**\n * Definition for singly-linked list.\n * class ListNode {\n * val: number\n * next: ListNode | null\n * constructor(val?: number, next?: ListNode | null) {\n * this.val = (val===undefined ? 0 : val)\n * this.next = (next===undefined ? null : next)\n * }\n * }\n */\n\nfunction mergeKLists(lists: Array): ListNode | null {\n \n};", "__typename": "CodeSnippetNode" }, { "lang": "PHP", "langSlug": "php", "code": "/**\n * Definition for a singly-linked list.\n * class ListNode {\n * public $val = 0;\n * public $next = null;\n * function __construct($val = 0, $next = null) {\n * $this->val = $val;\n * $this->next = $next;\n * }\n * }\n */\nclass Solution {\n\n /**\n * @param ListNode[] $lists\n * @return ListNode\n */\n function mergeKLists($lists) {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Swift", "langSlug": "swift", "code": "/**\n * Definition for singly-linked list.\n * public class ListNode {\n * public var val: Int\n * public var next: ListNode?\n * public init() { self.val = 0; self.next = nil; }\n * public init(_ val: Int) { self.val = val; self.next = nil; }\n * public init(_ val: Int, _ next: ListNode?) { self.val = val; self.next = next; }\n * }\n */\nclass Solution {\n func mergeKLists(_ lists: [ListNode?]) -> ListNode? {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Kotlin", "langSlug": "kotlin", "code": "/**\n * Example:\n * var li = ListNode(5)\n * var v = li.`val`\n * Definition for singly-linked list.\n * class ListNode(var `val`: Int) {\n * var next: ListNode? = null\n * }\n */\nclass Solution {\n fun mergeKLists(lists: Array): ListNode? {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Dart", "langSlug": "dart", "code": "/**\n * Definition for singly-linked list.\n * class ListNode {\n * int val;\n * ListNode? next;\n * ListNode([this.val = 0, this.next]);\n * }\n */\nclass Solution {\n ListNode? mergeKLists(List lists) {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Go", "langSlug": "golang", "code": "/**\n * Definition for singly-linked list.\n * type ListNode struct {\n * Val int\n * Next *ListNode\n * }\n */\nfunc mergeKLists(lists []*ListNode) *ListNode {\n \n}", "__typename": "CodeSnippetNode" }, { "lang": "Ruby", "langSlug": "ruby", "code": "# Definition for singly-linked list.\n# class ListNode\n# attr_accessor :val, :next\n# def initialize(val = 0, _next = nil)\n# @val = val\n# @next = _next\n# end\n# end\n# @param {ListNode[]} lists\n# @return {ListNode}\ndef merge_k_lists(lists)\n \nend", "__typename": "CodeSnippetNode" }, { "lang": "Scala", "langSlug": "scala", "code": "/**\n * Definition for singly-linked list.\n * class ListNode(_x: Int = 0, _next: ListNode = null) {\n * var next: ListNode = _next\n * var x: Int = _x\n * }\n */\nobject Solution {\n def mergeKLists(lists: Array[ListNode]): ListNode = {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Rust", "langSlug": "rust", "code": "// Definition for singly-linked list.\n// #[derive(PartialEq, Eq, Clone, Debug)]\n// pub struct ListNode {\n// pub val: i32,\n// pub next: Option>\n// }\n// \n// impl ListNode {\n// #[inline]\n// fn new(val: i32) -> Self {\n// ListNode {\n// next: None,\n// val\n// }\n// }\n// }\nimpl Solution {\n pub fn merge_k_lists(lists: Vec>>) -> Option> {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Racket", "langSlug": "racket", "code": "; Definition for singly-linked list:\n#|\n\n; val : integer?\n; next : (or/c list-node? 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Most standard library headers are already included automatically for your convenience.

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