Linked ListMedium

19. Sort a Linked List (Merge Sort) ⭐

Optimal O(n log n) sorting using divide-and-conquer: splits at middle with slow/fast, then merges sublists.

Time O(n log n) Space O(log n)

Live loop — open the studio to scrub, add your own array, or race it in Battle Arena.

Asked in interviews at

Goldman SachsAdobeSalesforce

Reference implementation (Python)

def sort_list(head):
    if not head or not head.next:
        return head
    slow, fast = head, head.next
    while fast and fast.next:
        slow, fast = slow.next, fast.next.next
    mid = slow.next
    slow.next = None
    left = sort_list(head)
    right = sort_list(mid)
    return merge(left, right)

Embed this visualization

Drop a live, looping 19. Sort a Linked List (Merge Sort) ⭐ canvas into a blog post or course page.

<iframe src="/embed/sort-linked-list" width="100%" height="380" style="border:1px solid #e6e8ec;border-radius:14px" loading="lazy" title="3D algorithm visualization by CodeWithMunnaX"></iframe>

Frequently asked

What is the time and space complexity of 19. Sort a Linked List (Merge Sort) ⭐?

19. Sort a Linked List (Merge Sort) ⭐ runs in O(n log n) time and O(log n) auxiliary space.

Is the 19. Sort a Linked List (Merge Sort) ⭐ visualizer free?

The core 3D visualizer, Web Audio chimes and step intuition are free. A one-time ₹49 Pro Pass unlocks advanced algorithms, large custom arrays, Battle Arena and reel export.

Which companies ask 19. Sort a Linked List (Merge Sort) ⭐ in interviews?

19. Sort a Linked List (Merge Sort) ⭐ shows up in interviews at Goldman Sachs, Adobe, Salesforce.

How does the 3D visualization of 19. Sort a Linked List (Merge Sort) ⭐ work?

Each array value becomes a 3D pillar whose height maps to its value. Comparisons glow amber, swaps flash red, and settled elements lock green while a floating pointer badge tracks the active index — synchronized line-by-line with the Python code.