{"id":6962,"date":"2025-06-18T17:33:24","date_gmt":"2025-06-18T12:03:24","guid":{"rendered":"https:\/\/namastedev.com\/blog\/?p=6962"},"modified":"2025-06-18T20:31:48","modified_gmt":"2025-06-18T15:01:48","slug":"rotate-list","status":"publish","type":"post","link":"https:\/\/namastedev.com\/blog\/rotate-list\/","title":{"rendered":"Rotate List"},"content":{"rendered":"\n<!-- PrismJS for Syntax Highlighting -->\n<link href=\"https:\/\/cdn.jsdelivr.net\/npm\/prismjs@1.29.0\/themes\/prism-tomorrow.min.css\" rel=\"stylesheet\">\n<script src=\"https:\/\/cdn.jsdelivr.net\/npm\/prismjs@1.29.0\/prism.min.js\"><\/script>\n<script src=\"https:\/\/cdn.jsdelivr.net\/npm\/prismjs@1.29.0\/plugins\/autoloader\/prism-autoloader.min.js\"><\/script>\n\n<style>\n  .wp_blog_main-heading {\n    text-align: center;\n    font-size: 2.4rem;\n    color: #E58C32;\n    margin-top: 2.5rem;\n    font-weight: bold;\n  }\n\n  .wp_blog_explanation,\n  .wp_blog_code-tabs-container {\n    max-width: 940px;\n    margin: 2rem auto;\n    padding: 2rem;\n    border-radius: 12px;\n    background-color: #f9fafb;\n  }\n\n  .wp_blog_explanation h2 {\n    font-size: 1.4rem;\n    color: #E58C32;\n    margin-bottom: 0.75rem;\n  }\n\n  .wp_blog_explanation p,\n  .wp_blog_explanation li {\n    font-size: 1.05rem;\n    line-height: 1.7;\n    margin: 0.5rem 0;\n    color: #1f2937;\n  }\n\n  .wp_blog_explanation code {\n    padding: 3px 6px;\n    border-radius: 4px;\n    background: #e5e7eb;\n    font-family: 'Courier New', monospace;\n  }\n\n  .wp_blog_code-tabs-header {\n    display: flex;\n    flex-wrap: wrap;\n    gap: 0.5rem;\n    margin-bottom: 1rem;\n  }\n\n  .wp_blog_code-tab-button {\n    padding: 0.6rem 1.2rem;\n    border: 1px solid #E58C32;\n    color: #E58C32;\n    border-radius: 50px;\n    font-weight: 600;\n    cursor: pointer;\n    background-color: white;\n    transition: background 0.3s ease, color 0.3s ease;\n  }\n\n  .wp_blog_code-tab-button.active {\n    background: #E58C32;\n    color: white;\n  }\n\n  .wp_blog_code-tab-content {\n    display: none;\n    background: #111827;\n    border-radius: 12px;\n  }\n\n  .wp_blog_code-tab-content.active {\n    display: block;\n  }\n\n  .wp_blog_code-tab-content pre {\n    margin: 0;\n    padding: 1.5rem;\n    font-size: 1rem;\n    overflow-x: auto;\n    color: #f3f4f6;\n    background: #111827;\n    border-radius: 12px;\n  }\n<\/style>\n<div class=\"wp_blog_explanation\">\n  <h2>Problem Statement:<\/h2>\n  <p>Given the head of a linked list, rotate the list to the right by <code>k<\/code> places.<\/p>\n\n  <h2>Examples:<\/h2>\n  <p><strong>Input:<\/strong> head = [1,2,3,4,5], k = 2<br><strong>Output:<\/strong> [4,5,1,2,3]<\/p>\n  <p><strong>Input:<\/strong> head = [0,1,2], k = 4<br><strong>Output:<\/strong> [2,0,1]<\/p>\n\n  <h2>Constraints:<\/h2>\n  <ul>\n    <li>The number of nodes in the list is in the range [0, 500].<\/li>\n    <li>-100 &le; Node.val &le; 100<\/li>\n    <li>0 &le; k &le; 2 * 10<sup>9<\/sup><\/li>\n  <\/ul>\n\n  <h2>Approach:<\/h2>\n  <ul>\n    <li>First, compute the length of the list.<\/li>\n    <li>Adjust <code>k<\/code> using modulo: <code>k = k % length<\/code>.<\/li>\n    <li>Use two pointers: move one <code>k<\/code> steps ahead, then move both until the first reaches the end.<\/li>\n    <li>Rewire the pointers to rotate the list, breaking it at the new tail.<\/li>\n  <\/ul>\n<\/div>\n\n<div class=\"wp_blog_code-tabs-container\">\n  <div class=\"wp_blog_code-tabs-header\">\n    <button class=\"wp_blog_code-tab-button active\" data-lang=\"js\">JavaScript<\/button>\n    <button class=\"wp_blog_code-tab-button\" data-lang=\"c\">C<\/button>\n    <button class=\"wp_blog_code-tab-button\" data-lang=\"cpp\">C++<\/button>\n    <button class=\"wp_blog_code-tab-button\" data-lang=\"java\">Java<\/button>\n    <button class=\"wp_blog_code-tab-button\" data-lang=\"py\">Python<\/button>\n    <button class=\"wp_blog_code-tab-button\" data-lang=\"csharp\">C#<\/button>\n  <\/div>\n\n  <div class=\"wp_blog_code-tab-content active\" data-lang=\"js\">\n    <pre><code class=\"language-javascript\">\nvar rotateRight = function(head, k) {\n    if (!head || !head.next || k === 0) return head;\n    \n    let length = 1;\n    let tail = head;\n    while (tail.next) {\n        tail = tail.next;\n        length++;\n    }\n\n    k = k % length;\n    if (k === 0) return head;\n\n    let stepsToNewHead = length - k;\n    let prev = null;\n    let curr = head;\n    while (stepsToNewHead--) {\n        prev = curr;\n        curr = curr.next;\n    }\n\n    prev.next = null;\n    tail.next = head;\n    return curr;\n};\n    <\/code><\/pre>\n  <\/div>\n\n  <div class=\"wp_blog_code-tab-content\" data-lang=\"c\">\n    <pre><code class=\"language-c\">\nstruct ListNode* rotateRight(struct ListNode* head, int k) {\n    if (!head || !head->next || k == 0) return head;\n\n    int length = 1;\n    struct ListNode* tail = head;\n    while (tail->next) {\n        tail = tail->next;\n        length++;\n    }\n\n    k = k % length;\n    if (k == 0) return head;\n\n    int steps = length - k;\n    struct ListNode* prev = NULL;\n    struct ListNode* curr = head;\n    while (steps--) {\n        prev = curr;\n        curr = curr->next;\n    }\n\n    prev->next = NULL;\n    tail->next = head;\n    return curr;\n}\n    <\/code><\/pre>\n  <\/div>\n\n  <div class=\"wp_blog_code-tab-content\" data-lang=\"cpp\">\n    <pre><code class=\"language-cpp\">\nclass Solution {\npublic:\n    ListNode* rotateRight(ListNode* head, int k) {\n        if (!head || !head->next || k == 0) return head;\n\n        int length = 1;\n        ListNode* tail = head;\n        while (tail->next) {\n            tail = tail->next;\n            length++;\n        }\n\n        k = k % length;\n        if (k == 0) return head;\n\n        int steps = length - k;\n        ListNode* prev = nullptr;\n        ListNode* curr = head;\n        while (steps--) {\n            prev = curr;\n            curr = curr->next;\n        }\n\n        prev->next = nullptr;\n        tail->next = head;\n        return curr;\n    }\n};\n    <\/code><\/pre>\n  <\/div>\n\n  <div class=\"wp_blog_code-tab-content\" data-lang=\"java\">\n    <pre><code class=\"language-java\">\nclass Solution {\n    public ListNode rotateRight(ListNode head, int k) {\n        if (head == null || head.next == null || k == 0) return head;\n\n        int length = 1;\n        ListNode tail = head;\n        while (tail.next != null) {\n            tail = tail.next;\n            length++;\n        }\n\n        k = k % length;\n        if (k == 0) return head;\n\n        int steps = length - k;\n        ListNode prev = null;\n        ListNode curr = head;\n        while (steps-- > 0) {\n            prev = curr;\n            curr = curr.next;\n        }\n\n        prev.next = null;\n        tail.next = head;\n        return curr;\n    }\n}\n    <\/code><\/pre>\n  <\/div>\n\n  <div class=\"wp_blog_code-tab-content\" data-lang=\"py\">\n    <pre><code class=\"language-python\">\nclass Solution(object):\n    def rotateRight(self, head, k):\n        if not head or not head.next or k == 0:\n            return head\n\n        length = 1\n        tail = head\n        while tail.next:\n            tail = tail.next\n            length += 1\n\n        k = k % length\n        if k == 0:\n            return head\n\n        steps = length - k\n        prev = None\n        curr = head\n        for _ in range(steps):\n            prev = curr\n            curr = curr.next\n\n        prev.next = None\n        tail.next = head\n        return curr\n    <\/code><\/pre>\n  <\/div>\n\n  <div class=\"wp_blog_code-tab-content\" data-lang=\"csharp\">\n    <pre><code class=\"language-csharp\">\npublic class Solution {\n    public ListNode RotateRight(ListNode head, int k) {\n        if (head == null || head.next == null || k == 0) return head;\n\n        int length = 1;\n        ListNode tail = head;\n        while (tail.next != null) {\n            tail = tail.next;\n            length++;\n        }\n\n        k = k % length;\n        if (k == 0) return head;\n\n        int steps = length - k;\n        ListNode prev = null;\n        ListNode curr = head;\n        while (steps-- > 0) {\n            prev = curr;\n            curr = curr.next;\n        }\n\n        prev.next = null;\n        tail.next = head;\n        return curr;\n    }\n}\n    <\/code><\/pre>\n  <\/div>\n<\/div>\n\n<script>\n  document.addEventListener('DOMContentLoaded', () => {\n    const buttons = document.querySelectorAll('.wp_blog_code-tab-button');\n    const contents = document.querySelectorAll('.wp_blog_code-tab-content');\n    buttons.forEach(button => {\n      button.addEventListener('click', () => {\n        const lang = button.getAttribute('data-lang');\n        buttons.forEach(btn => btn.classList.remove('active'));\n        contents.forEach(content => content.classList.remove('active'));\n        button.classList.add('active');\n        document.querySelector(`.wp_blog_code-tab-content[data-lang=\"${lang}\"]`).classList.add('active');\n      });\n    });\n  });\n<\/script>\n","protected":false},"excerpt":{"rendered":"<p>Problem Statement: Given the head of a linked list, rotate the list to the right by k places. Examples: Input: head = [1,2,3,4,5], k = 2Output: [4,5,1,2,3] Input: head = [0,1,2], k = 4Output: [2,0,1] Constraints: The number of nodes in the list is in the range [0, 500]. -100 &le; Node.val &le; 100 0<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[260,176,811,810,174,172,173],"tags":[],"class_list":["post-6962","post","type-post","status-publish","format-standard","category-c-c-plus-plus","category-csharp","category-data-structures-and-algorithms","category-dsa","category-java","category-javascript","category-python"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/posts\/6962","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/comments?post=6962"}],"version-history":[{"count":1,"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/posts\/6962\/revisions"}],"predecessor-version":[{"id":6964,"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/posts\/6962\/revisions\/6964"}],"wp:attachment":[{"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/media?parent=6962"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/categories?post=6962"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/namastedev.com\/blog\/wp-json\/wp\/v2\/tags?post=6962"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}