- Executors
-
Learn
Learn Python Runnable examples, NumPy, pandas, and more Learn AINeural networks, ML and LLMs from scratch Learn C & C++ Pointers, memory, STL, and modern C++ Learn C#C# basics, OOP, LINQ, async, and .NET exercises Python Algorithms Search, sorting, recursion, and visualizers O(n) C & C++ Algorithms Compare algorithms implemented in C and C++
- ChallengesNew
Ai coding challenges
Practise ai with 47 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 · 19 Medium · 24 Hard · 4
Skills you'll practise: Gradient descentBackpropagationChain ruleDecision treesRegressionTransformersA* searchActivationsAdamAlpha-beta pruningAttentionBPE
- Python · C++ · C#
- Automated tests
- AI code review
- Community solutions
- 226
- Challenges
- 2
- Solutions shared
- 3
- Languages
All challenges
Search by topic, language, or difficulty.
Medium
A* Search on a Weighted Grid
Find the cheapest path across a grid of terrain costs with A*, the search algorithm behind game and robot pathfinding.
You'll learn
A* searchHeuristics
No solutions yet
Medium
Value Iteration
Compute how valuable each state of a Markov decision process is by repeatedly applying the Bellman optimality update.
You'll learn
Bellman equationMDPs
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
Medium
Alpha-Beta Pruning
Evaluate a game tree with minimax and alpha-beta pruning, and count how many leaves the search really looks at.
You'll learn
Alpha-beta pruningGame search
No solutions yet
Medium
Q-Learning Updates
Apply the Q-learning update to a stream of experiences and watch rewards flow back to earlier states.
You'll learn
Q-learningDiscounted rewards
No solutions yet
Easy
Epsilon-Greedy Multi-Armed Bandit
Balance exploration and exploitation on a multi-armed bandit with epsilon-greedy action selection.
You'll learn
Explore vs exploitBandits
No solutions yet
Medium
Forward Propagation in a Two-Layer Network
Run inputs through a hidden ReLU layer and a sigmoid output layer.
You'll learn
Forward passMulti-layer networks
No solutions yet
Medium
Perceptron Learning Algorithm
Train the original perceptron, which updates its weights only when it makes a mistake.
You'll learn
PerceptronOnline learning
No solutions yet
Medium
Gradients of a Single Neuron
Use the chain rule to find how the loss changes with each weight and the bias of a sigmoid neuron.
You'll learn
Chain ruleGradients
No solutions yet
Easy
Activation Functions
Apply sigmoid, ReLU, Leaky ReLU or tanh to every value in a list.
You'll learn
SigmoidReLU and tanh
No solutions yet
Easy
Loss Functions: MSE, MAE and Cross-Entropy
Measure how wrong a model's predictions are with mean squared error, mean absolute error or binary cross-entropy.
You'll learn
MSECross-entropy
No solutions yet
Medium
Layer Normalization
Normalize each row to zero mean and unit variance, then scale and shift it, as every Transformer block does.
You'll learn
Layer normTransformers
No solutions yet
Easy
Single Artificial Neuron
Compute the output of one neuron: weighted sum of the inputs plus a bias, passed through sigmoid.
You'll learn
NeuronsWeighted sums
No solutions yet
Hard
Backpropagation in a Two-Layer Network
Compute every weight and bias gradient of a network with one sigmoid hidden layer and one sigmoid output.
You'll learn
BackpropagationChain rule
No solutions yet
Easy
Derivatives of Activation Functions
Compute the derivative of sigmoid, ReLU, Leaky ReLU or tanh at each value, the slopes backpropagation needs.
You'll learn
DerivativesBackpropagation
No solutions yet
Medium
Dense Layer Forward Pass
Compute the outputs of a fully connected layer of neurons with a choice of activation.
You'll learn
Dense layersActivations
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
Medium
Minimax Tic-Tac-Toe
Pick the perfect tic-tac-toe move by searching the whole game tree with minimax.
You'll learn
MinimaxGame trees
No solutions yet
Browse by topic
- Beginner 95
- Ai 47
- Machine Learning 42
- Strings 36
- Arrays 31
- Math 21
- Simulation 19
- Neural Networks 17
- Numbers 16
- Advanced 15
- Dynamic Programming 12
- Parsing 12
- Competitive Programming 10
- Conditions 9
- Design Patterns 8
- Graphs 8
- Grids 8
- Loops 8
- Recursion 7
- Combinatorics 6
- Number Theory 6
- Sorting 6
- Functions 5
- Greedy 5
- Nested Loops 5
- Sequences 5
- Stacks 5
- Variables 5
- Algorithms 4
- Data Structures 4
- Geometry 4
- Patterns 4
- Dictionaries 3
- Fractions 3
- Reinforcement Learning 3
- Sliding Window 3
- Trees 3