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Premium · 2026 interview format

Spot the AI's bug: Reverse a linked list

Meta and Google now hand you an AI assistant in the coding round and score whether you can catch what it got wrong. This Linked List drill shows you an AI-written solution; your job is to give the verdict, find the flaw, and see the input that breaks it.

The drill

Given the head of a singly linked list, reverse it and return the new head.

The AI's solution, your verdict, and the reveal unlock with Premium.

The AI-assisted round is the newest thing in FAANG hiring, and almost nothing out there trains beginners for it. These drills do, woven right into the guided path.

What you get

  • Spot-the-AI's-bug drills interleaved through every pattern unit: verdict, find the flaw, prove it
  • The full guided learning path: concept lessons, drills, graded tests, and cold-read capstones
  • Stop going blank on algorithm problems. The hint ladder walks you to the answer without spoiling it.
  • Know when to reach for each pattern. Every problem names the trigger so you spot it next time.
  • Write and run JS or Python in the browser with real test cases on every problem
  • Access every new problem, unit, drill, and pattern guide as they ship weekly
B
Big_Wolverine_7575Founding Member· unprompted on Reddit

“This app finally made it click. I tried NeetCode, CTCI, and YouTube for years and still couldn't solve Two Sum. The beginner mental models for the patterns are genuinely so helpful. THANK YOU.

Price locks in for life · First 100 only

Founding Member Deal

$29 / year

or $6 / month

LeetCode Premium is $159/year and doesn't teach you anything.

Less than one Udemy course, with guided problems instead of passive lectures.

One extra month of job searching costs more than a full year here.

Your price is locked in for life.

When the 100th founding spot closes, the price goes up for everyone who joins after. Your rate never changes, no matter how much the curriculum grows.

  • Every Spot-the-AI's-bug drill across all units
  • All 150 problems across 33 patterns, plus every new one
  • New problems, drills, and units weekly
  • Cancel anytime

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