{ "data": { "question": { "questionId": "2573", "questionFrontendId": "2487", "boundTopicId": null, "title": "Remove Nodes From Linked List", "titleSlug": "remove-nodes-from-linked-list", "content": "

You are given the head of a linked list.

\n\n

Remove every node which has a node with a greater value anywhere to the right side of it.

\n\n

Return the head of the modified linked list.

\n\n

 

\n

Example 1:

\n\"\"\n
\nInput: head = [5,2,13,3,8]\nOutput: [13,8]\nExplanation: The nodes that should be removed are 5, 2 and 3.\n- Node 13 is to the right of node 5.\n- Node 13 is to the right of node 2.\n- Node 8 is to the right of node 3.\n
\n\n

Example 2:

\n\n
\nInput: head = [1,1,1,1]\nOutput: [1,1,1,1]\nExplanation: Every node has value 1, so no nodes are removed.\n
\n\n

 

\n

Constraints:

\n\n\n", "translatedTitle": null, "translatedContent": null, "isPaidOnly": false, "difficulty": "Medium", "likes": 1244, "dislikes": 32, "isLiked": null, "similarQuestions": "[{\"title\": \"Reverse Linked List\", \"titleSlug\": \"reverse-linked-list\", \"difficulty\": \"Easy\", \"translatedTitle\": null}, {\"title\": \"Delete Node in a Linked List\", \"titleSlug\": \"delete-node-in-a-linked-list\", \"difficulty\": \"Medium\", \"translatedTitle\": null}, {\"title\": \"Next Greater Element I\", \"titleSlug\": \"next-greater-element-i\", \"difficulty\": \"Easy\", \"translatedTitle\": null}]", "exampleTestcases": "[5,2,13,3,8]\n[1,1,1,1]", "categoryTitle": "Algorithms", "contributors": [], "topicTags": [ { "name": "Linked List", "slug": "linked-list", "translatedName": null, "__typename": "TopicTagNode" }, { "name": "Stack", "slug": "stack", "translatedName": null, "__typename": "TopicTagNode" }, { "name": "Recursion", "slug": "recursion", "translatedName": null, "__typename": "TopicTagNode" }, { "name": "Monotonic Stack", "slug": "monotonic-stack", "translatedName": null, "__typename": "TopicTagNode" } ], "companyTagStats": null, "codeSnippets": [ { "lang": "C++", "langSlug": "cpp", "code": "/**\n * Definition for singly-linked list.\n * struct ListNode {\n * int val;\n * ListNode *next;\n * ListNode() : val(0), next(nullptr) {}\n * ListNode(int x) : val(x), next(nullptr) {}\n * ListNode(int x, ListNode *next) : val(x), next(next) {}\n * };\n */\nclass Solution {\npublic:\n ListNode* removeNodes(ListNode* head) {\n \n }\n};", "__typename": "CodeSnippetNode" }, { "lang": "Java", "langSlug": "java", "code": "/**\n * Definition for singly-linked list.\n * public class ListNode {\n * int val;\n * ListNode next;\n * ListNode() {}\n * ListNode(int val) { this.val = val; }\n * ListNode(int val, ListNode next) { this.val = val; this.next = next; }\n * }\n */\nclass Solution {\n public ListNode removeNodes(ListNode head) {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Python", "langSlug": "python", "code": "# Definition for singly-linked list.\n# class ListNode(object):\n# def __init__(self, val=0, next=None):\n# self.val = val\n# self.next = next\nclass Solution(object):\n def removeNodes(self, head):\n \"\"\"\n :type head: Optional[ListNode]\n :rtype: Optional[ListNode]\n \"\"\"\n ", "__typename": "CodeSnippetNode" }, { "lang": "Python3", "langSlug": "python3", "code": "# Definition for singly-linked list.\n# class ListNode:\n# def __init__(self, val=0, next=None):\n# self.val = val\n# self.next = next\nclass Solution:\n def removeNodes(self, head: Optional[ListNode]) -> Optional[ListNode]:\n ", "__typename": "CodeSnippetNode" }, { "lang": "C", "langSlug": "c", "code": "/**\n * Definition for singly-linked list.\n * struct ListNode {\n * int val;\n * struct ListNode *next;\n * };\n */\nstruct ListNode* removeNodes(struct ListNode* head) {\n \n}", "__typename": "CodeSnippetNode" }, { "lang": "C#", "langSlug": "csharp", "code": "/**\n * Definition for singly-linked list.\n * public class ListNode {\n * public int val;\n * public ListNode next;\n * public ListNode(int val=0, ListNode next=null) {\n * this.val = val;\n * this.next = next;\n * }\n * }\n */\npublic class Solution {\n public ListNode RemoveNodes(ListNode head) {\n \n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "JavaScript", "langSlug": "javascript", "code": "/**\n * Definition for singly-linked list.\n * function ListNode(val, next) {\n * this.val = (val===undefined ? 0 : val)\n * this.next = (next===undefined ? null : next)\n * }\n */\n/**\n * @param {ListNode} head\n * @return {ListNode}\n */\nvar removeNodes = function(head) {\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 removeNodes(head: ListNode | null): 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 $head\n * @return ListNode\n */\n function removeNodes($head) {\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 removeNodes(_ head: 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 removeNodes(head: ListNode?): 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? removeNodes(ListNode? head) {\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 removeNodes(head *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} head\n# @return {ListNode}\ndef remove_nodes(head)\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 removeNodes(head: 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 remove_nodes(head: Option>) -> 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? #f)\n(struct list-node\n (val next) #:mutable #:transparent)\n\n; constructor\n(define (make-list-node [val 0])\n (list-node val #f))\n\n|#\n\n(define/contract (remove-nodes head)\n (-> (or/c list-node? #f) (or/c list-node? #f))\n )", "__typename": "CodeSnippetNode" }, { "lang": "Erlang", "langSlug": "erlang", "code": "%% Definition for singly-linked list.\n%%\n%% -record(list_node, {val = 0 :: integer(),\n%% next = null :: 'null' | #list_node{}}).\n\n-spec remove_nodes(Head :: #list_node{} | null) -> #list_node{} | null.\nremove_nodes(Head) ->\n .", "__typename": "CodeSnippetNode" }, { "lang": "Elixir", "langSlug": "elixir", "code": "# Definition for singly-linked list.\n#\n# defmodule ListNode do\n# @type t :: %__MODULE__{\n# val: integer,\n# next: ListNode.t() | nil\n# }\n# defstruct val: 0, next: nil\n# end\n\ndefmodule Solution do\n @spec remove_nodes(head :: ListNode.t | nil) :: ListNode.t | nil\n def remove_nodes(head) do\n \n end\nend", "__typename": "CodeSnippetNode" } ], "stats": "{\"totalAccepted\": \"48.8K\", \"totalSubmission\": \"74.2K\", \"totalAcceptedRaw\": 48772, \"totalSubmissionRaw\": 74200, \"acRate\": \"65.7%\"}", "hints": [ "Iterate on nodes in reversed order.", "When iterating in reversed order, save the maximum value that was passed before." ], "solution": null, "status": null, "sampleTestCase": "[5,2,13,3,8]", "metaData": "{\n \"name\": \"removeNodes\",\n \"params\": [\n {\n \"name\": \"head\",\n \"type\": \"ListNode\"\n }\n ],\n \"return\": {\n \"type\": \"ListNode\"\n }\n}", "judgerAvailable": true, "judgeType": "large", "mysqlSchemas": [], "enableRunCode": true, "enableTestMode": false, "enableDebugger": true, "envInfo": "{\"cpp\": [\"C++\", \"

Compiled with clang 11 using the latest C++ 20 standard.

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Your code is compiled with level two optimization (-O2). AddressSanitizer is also enabled to help detect out-of-bounds and use-after-free bugs.

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Most standard library headers are already included automatically for your convenience.

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OpenJDK 17. Java 8 features such as lambda expressions and stream API can be used.

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Most standard library headers are already included automatically for your convenience.

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Includes Pair class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.

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Python 2.7.12.

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Most libraries are already imported automatically for your convenience, such as array, bisect, collections. If you need more libraries, you can import it yourself.

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For Map/TreeMap data structure, you may use sortedcontainers library.

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Note that Python 2.7 will not be maintained past 2020. For the latest Python, please choose Python3 instead.

\"], \"c\": [\"C\", \"

Compiled with gcc 8.2 using the gnu11 standard.

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Your code is compiled with level one optimization (-O1). AddressSanitizer is also enabled to help detect out-of-bounds and use-after-free bugs.

\\r\\n\\r\\n

Most standard library headers are already included automatically for your convenience.

\\r\\n\\r\\n

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1. Adding an item to a hash.\\r\\n

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\\r\\n

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2. Looking up an item in a hash:\\r\\n

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\\r\\n

\\r\\n\\r\\n

3. Deleting an item in a hash:\\r\\n

\\r\\nvoid delete_user(struct hash_entry *user) {\\r\\n    HASH_DEL(users, user);  \\r\\n}\\r\\n
\\r\\n

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C# 10 with .NET 6 runtime

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Node.js 16.13.2.

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Your code is run with --harmony flag, enabling new ES6 features.

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lodash.js library is included by default.

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Ruby 3.1

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Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms

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Swift 5.5.2.

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Go 1.21

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Python 3.10.

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For Map/TreeMap data structure, you may use sortedcontainers library.

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Scala 2.13.7.

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Kotlin 1.9.0.

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Dart 2.17.3

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