Pattern · Simulation

Simulation interview questions

107 simulation problems tagged across recent interview reports. Drilled most heavily by goldman sachs, google, and meta.

Founder's read

Simulation problems ask you to execute a process step-by-step, tracking state as it changes. You're not optimizing or searching, you're faithfully implementing the rules. With 107 problems in this pattern and Goldman Sachs asking 26 of them, simulation shows up constantly in live assessments. The twist: they seem easy until edge cases or state management trips you up mid-interview. StealthCoder keeps you from stalling on the variant you didn't drill.

Most-asked simulation problems

#ProblemDiff# Companies
01Asteroid CollisionMEDIUM24
02Design Tic-Tac-ToeMEDIUM13
03Fizz BuzzEASY13
04Backspace String CompareEASY12
05Add BinaryEASY11
06Add StringsEASY10
07Design a Text EditorHARD8
08Diagonal TraverseMEDIUM7
09Candy CrushMEDIUM6
10Car PoolingMEDIUM6
11Design Memory AllocatorMEDIUM6
12Find the Winner of the Circular GameMEDIUM6
13Add DigitsEASY3
14Count Operations to Obtain ZeroEASY3
15Design Snake GameMEDIUM3
16Find Winner on a Tic Tac Toe GameEASY3
17Average Waiting TimeMEDIUM2
18Calculate Amount Paid in TaxesEASY2
19Design Parking SystemEASY2
20Ant on the BoundaryEASY1
21Array TransformationEASY1
22Available Captures for RookEASY1
23Baseball GameEASY1
24Calculate Score After Performing InstructionsMEDIUM1
25Clear DigitsEASY1
26Concatenation of ArrayEASY1
27Count Collisions on a RoadMEDIUM1
28Count Integers With Even Digit SumEASY1
29Count Tested Devices After Test OperationsEASY1
30Count Unguarded Cells in the GridMEDIUM1
31Count Unhappy FriendsMEDIUM1
32Create Target Array in the Given OrderEASY1
33Cyclically Rotating a GridMEDIUM1
34Decode the Slanted CiphertextMEDIUM1
35Determine the Winner of a Bowling GameEASY1
36Distribute Elements Into Two Arrays IEASY1
37Distribute Elements Into Two Arrays IIHARD1
38Divide a String Into Groups of Size kEASY1
39Double Modular ExponentiationMEDIUM1
40Equal Row and Column PairsMEDIUM1
41Faulty KeyboardEASY1
42Find Mirror Score of a StringMEDIUM1
43Find Score of an Array After Marking All ElementsMEDIUM1
44Find the Array Concatenation ValueEASY1
45Find the Child Who Has the Ball After K SecondsEASY1
46Find The First Player to win K Games in a RowMEDIUM1
47Find the Minimum Amount of Time to Brew PotionsMEDIUM1
48Find the Winner of an Array GameMEDIUM1
49Find Three Consecutive Integers That Sum to a Given NumberMEDIUM1
50Find Triangular Sum of an ArrayMEDIUM1

Showing top 50 of 107 simulation problems by # companies asking.

The hedge for the live OA

You can't drill every simulation variant before the assessment. StealthCoder runs invisibly during screen share and solves whichever variant they throw at you. No browser extension. No detection signature. Built by a senior engineer who knows the OA is theater. This is the script.

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What this means

Simulation problems are recognized by their procedural language: 'perform', 'apply', 'execute', 'simulate'. You read a sequence of instructions and track how some data structure changes. Common subtypes include string manipulations (backspace-string-compare, add-strings), collision detection (asteroid-collision), and instruction execution (calculate-score-after-performing-instructions). The trap is sloppy bookkeeping: off-by-one errors in index management, forgetting to reset counters, or mishandling edge cases like empty inputs. Google, Meta, and Goldman Sachs hammer these heavily. Drill them in order of complexity: simple arithmetic sims first (add-binary, add-digits), then container and collision problems, then instruction batches. When a simulation variant lands in your live OA and you're not sure how to track state cleanly, StealthCoder solves it invisibly.

Companies that hire most on simulation

The honest play

107 simulation problems. You won't drill them all. Pass anyway.

Simulation is one of the patterns interviews actually filter on. Memorizing every variant in a week is a fantasy. StealthCoder is the hedge: an AI overlay invisible during screen share. It reads the problem and surfaces a working solution in under 2 seconds, no matter which simulation flavor lands in your live OA. Built by a senior engineer who knows the OA is theater. This is the script. Works on HackerRank, CodeSignal, CoderPad, and Karat.

Simulation interview FAQ

How many simulation problems should I drill before an interview?+

With 107 problems in the pattern, aim for 15-20 across different subtypes: string operations, array modifications, and instruction execution. Focus on problems from Goldman Sachs (26), Google (21), and Meta (21) since they ask most heavily. Quality matters more than count; understand state tracking, not just pattern-matching.

Is simulation the most important pattern for Goldman Sachs?+

No, but it's substantial. Goldman Sachs asks 26 simulation problems. They also test arrays, sorting, hashing, and dynamic programming. Treat simulation as a high-frequency, medium-difficulty block worth solid prep, not your bottleneck.

How do I recognize a simulation problem in a live assessment?+

Look for imperative language: 'perform these operations in order', 'apply the rule', 'execute each step'. You're handed rules and a starting state, then you execute. Problems like backspace-string-compare and baseball-game are classic signals. No hidden optimization, just faithful execution.

Which company drills simulation the hardest?+

Goldman Sachs leads with 26 problems. Google and Meta each ask 21. Capital One, Bloomberg, and Zoho ask 20, 19, and 19 respectively. If you're targeting Goldman Sachs, simulation is a priority block.

What's the biggest mistake in simulation problems?+

Sloppy state tracking. Candidates forget to reset counters, mismandle indices, or skip edge cases like empty strings or single elements. Walk through examples by hand first. Use a debugger if you're unsure. Simulation rewards precision over cleverness.

Problem and frequency data sourced from public community-maintained interview-report repos. Problems and trademarks © LeetCode.