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Simulation coding challenges
Practise simulation with 19 coding challenges, from easy to hard. Every challenge runs in your browser with instant tests, an AI review of your code and community solutions to compare.
Easy · 12 Medium · 6 Hard · 1
Skills you'll practise: PolymorphismAmortised costBusiness rulesCommand processingConcurrencyDecorator patternDictionariesDirection vectorsDynamic arraysEncapsulationEvolutionary searchFacade pattern
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Medium
Game of Life Step
Advance Conway's Game of Life by one generation.
You'll learn
Grid simulationNeighbor counting
No solutions yet
Easy
Collatz Sequence
Follow the halve-or-triple-and-add-one rule until reaching 1.
You'll learn
While loopsStep counting
No solutions yet
Medium
Robot Command Simulator
Move a robot using L (turn left 90 degrees), R (turn right 90 degrees), and A (advance one step).
You'll learn
Direction vectorsCommand processing
No solutions yet
Hard
Hotel Room Allocation
Assign arriving groups in order.
You'll learn
Range maximum queriesPoint updates
No solutions yet
Medium
One Generation of a Genetic Algorithm
Breed the next generation of bit strings with tournament selection, single-point crossover and mutation.
You'll learn
Genetic algorithmsEvolutionary search
No solutions yet
Easy
Markov Chain State Distribution
Propagate a probability distribution through a Markov chain's transition matrix for a number of steps.
You'll learn
Markov chainsProbability
No solutions yet
Easy
Checkout Facade
Hide stock checks and price totals behind one simple checkout call.
You'll learn
Facade patternValidation
No solutions yet
Easy
One Shared Configuration
Simulate a singleton settings object: every part of the program reads and writes the same instance.
You'll learn
SingletonShared state
No solutions yet
Medium
Parallel Task Completion Order
Run tasks concurrently with at most k at a time and report the order in which they finish.
You'll learn
ConcurrencyPriority queues
No solutions yet
Medium
Weekly Payroll
Total a week's pay for salaried, hourly and commission employees, each paid by its own rule.
You'll learn
PolymorphismOvertime math
No solutions yet
Easy
Event Subscribers
Deliver events to the subscribers of each topic, observer style, and count what everyone receives.
You'll learn
Observer patternDictionaries
No solutions yet
Easy
Price Decorators
Wrap a base price in discount, tax, shipping and coupon decorators applied in order.
You'll learn
Decorator patternPercentages
No solutions yet
Easy
Notification Costs
Send messages through email, SMS and push channels that each compute their own cost.
You'll learn
PolymorphismInteger division
No solutions yet
Easy
Bank Account Rules
Protect an account's balance behind deposit and withdraw rules, rejecting invalid operations.
You'll learn
EncapsulationBusiness rules
No solutions yet
Easy
Linked List Operations
Simulate a linked list: add at either end, remove from the front or by value, and reverse it.
You'll learn
Linked listsSimulation
No solutions yet
Easy
Growing a Dynamic Array
Simulate how a dynamic array doubles its capacity and count the reallocations and copied elements.
You'll learn
Dynamic arraysAmortised cost
No solutions yet
Easy
Vehicle Tolls
Charge tolls for motorbikes, cars and trucks where trucks extend the basic vehicle rule with axles.
You'll learn
InheritanceMethod overriding
No solutions yet
Easy
To-Do List
Keep a list of tasks: add them, mark them done, remove them and report what is still pending.
You'll learn
Typed collectionsRecords
No solutions yet
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