List of the tags used for the puzzles

Tag name Category # Puzzles
2D array FUNDAMENTALS 26 Sandpile addition     1010(1)     Magic Square     Count of Primes in a number grid     Number of paths between 2 points     Lumen     Forest Fire     Battleship     Coders of the Realm - 1v1     Coders of the Realm     TicTacToe     Rock-Paper-Scissors War     Sudoku Validator     A Game of Go     Spring Challenge 2020     The lost child.Episode-1     Chess board analyzer     Dungeons and Maps     Flip The Sign     Reverse Minesweeper     Custom Game of Life     Can you save the forest - Episode 1     Substitution Encoding     Object Insertion     Folding a Note     Wave Function Collapse (sans Shannon)    
3D ADVANCED 5 Detective Pikaptcha EP4     Blockout     Let's make a cheap ASCII 3D engine!     Dice Duel     ASCII cube    
5% 2 TryAngle Catch     Dice Duel    
A* ADVANCED 4 A-star exercise     11-puzzle     Jump Point Search - Preprocessing     Jump Point Search - Runtime    
Algebra FUNDAMENTALS 3 Quaternion Multiplication     Expand the polynomial     Jumping Frogs    
AM/PM 1 Railway Station Clock    
angle FUNDAMENTALS 1 Windmill problem    
Arithmetic FUNDAMENTALS 21 Sum of divisors     Simple fraction to mixed number     Carmichael numbers     Divide the factorial     Balanced ternary computer: encode     Execution Circle     Highest truncated pyramid     The River II.     Magic count of numbers     Polydivisible number     De-FizzBuzzer     ISBN Check digit     Factorials of primes decomposition     The Total is Right - Weird edition     Remainder Fantasy     Flower beds     Number derivation     Nuggets numbers     Divisibility of Fibonacci numbers sum     Railway Station Clock     Cooking passion    
Arithmetics FUNDAMENTALS 0
Array forbidden 1 Graffiti on the fence    
Arrays FUNDAMENTALS 21 Temperatures     ASCII Art     Stock Exchange Losses     Temperatures     Monday Tuesday Happy Days     Simple Awalé     Bingo!     Pirate's treasure     Equalizing arrays     Rectangle Partition     Big Bang Theory - Sheldon's Array Puzzle     Rock Paper Scissors Lizard Spock     Unique Prefixes     Inversion count     Nurikabe     Fractal Image Recognition     Binary image     Personal Best     Detective Geek     Treasure hunt     FireControl    
ascii 1 Hidden Messages In Images    
Ascii Art INTERMEDIATE 18 May the Triforce be with you!     ASCII ART : Glass Stacking     Vortex     Self-driving car testing     Cards castle     Highest truncated pyramid     Ghost Legs     Propositions in Frege’s ideography     Crossword     7-segment scanner     Particle Detection with Cloud Chamber     Mountain Map     Let's make a cheap ASCII 3D engine!     Mountain Map Convergence     Longest Road     ASCII cube     Shadow Casting     Where's Wally    
Autoscaling 1 Simple auto-scaling    
Average FUNDAMENTALS 1 Dolbear's Law    
Backtracking ADVANCED 11 The Bridge     The Fall - Episode 2     The Fall - Episode 3     There is no Spoon - Episode 2     Winamax Sponsored Contest     Ticket to Ride: Europe     Neighbor-Sum Grids     Sudoku Solver     Surakarta     Futoshiki Solver     Kakuro Solver    
Ballistics 1 Legendary Archer Octavius    
barcode INTERMEDIATE 0
Barycenters INTERMEDIATE 1 Power of Thor - Episode 2    
Beam Search ADVANCED 5 Search Race     SameGame     2048     Can you save the forest - Episode 1     Can you save the forest - Episode 2    
Bezout's identity ADVANCED 1 Jumping Frogs    
BFS ADVANCED 16 Death First Search - Episode 1     The Labyrinth     Surface     2.5D maze     Hypersonic     Flood fill Example     Paper labyrinth     Locked in gear     The lost child.Episode-1     English length units conversion     Sokoban     Fall Challenge 2020     Cooperative Mate with Rook     Train passenger     Catching Up     River Crossing    
Binary representation 1 Binary Sequence    
Binary search ADVANCED 3 Shadows of the Knight - Episode 1     Shadows of the Knight - Episode 2     Binary Extension    
Binary Tree ADVANCED 4 Rational Number Tree     Binary Search Tree Traversal     Tree Paths     Binary Tree Visual    
Bitboarding ADVANCED 5 Breakthrough     Othello     Clobber     Amazons     Lines Of Action    
bitwise 1 Hidden Messages In Images    
Blood Types 1 Blood Types    
bot-programming 1 Clash of Bots    
brainfuck 1 What the Brainfuck !    
Bresenham's algorithm ADVANCED 1 Cultist Wars    
Brute-force INTERMEDIATE 10 Vox Codei - Episode 1     Vox Codei - Episode 2     Near-Palindromes     Depot organization     The Total is Right - Weird edition     Neighbor-Sum Grids     Hooch Clash     Smooth!     Kakuro Solver     Lost astronaut    
Byte-pair 1 Byte pair encoding    
Card game 0
Card games 1 Legends of Code & Magic    
Cards 1 🃏 FreeCell 🃏    
CG Funge 1 CGFunge Prime    
Chebyshev distance 1 Sweet spot    
Check-digit FUNDAMENTALS 3 ISBN Check digit     Credit Card Verifier (Luhn’s algorithm)     Barcode scanner    
chess 9 Harmless Rooks     Rooks Movements     Knights Jam     Chess board analyzer     Chess     Is the King In Check? (Part 1)     Cooperative Mate with Rook     Is the King In Check? (Part 2)     Adversarial Mate with Rook    
Chocolate 1 Goro Want Chocolate    
cinematics 1 Asteroids    
Cipher ADVANCED 2 Hacking at RobberCity     Caesar is the chief    
Classic board games 0
Clock 1 Railway Station Clock    
clustering 1 Virus spreading and clustering    
Collision Detection ADVANCED 2 Darts     Snooker Ball Collision    
Combination puzzle ADVANCED 1 Knights Jam    
Combinations 1 Kids Blocks    
Combinatorics ADVANCED 8 OneWay City     Count as I count     Bulls and Cows 2     Map Colorations     Kakuro Solver     if then else     Prime Fractals in Pascal's Triangle     Wave Function Collapse (sans Shannon)    
Complexity INTERMEDIATE 1 Chained Matrix Products    
Compression ADVANCED 5 Ancestors & Descendants     Paper labyrinth     Huffman Code     Byte pair encoding     Fax machine    
Condition FUNDAMENTALS 0
Conditions FUNDAMENTALS 45 Power of Thor - Episode 1     Temperatures     Unary     MIME Type     The Fall - Episode 1     Stock Exchange Losses     Scrabble     Mars Lander - Episode 1     Onboarding     Don't Panic - Episode 1     Don't Panic     Power of Thor     Temperatures     Othello     Texas Holdem     Monday Tuesday Happy Days     Hidden word     The River I.     Simple Awalé     Morellet’s random lines     Code4Life     Simplified Monopoly™ Turns Prediction     Brackets, Extended Edition     Ghost Legs     Pirate's treasure     Guessing n Cheating     Rooks Movements     The Dart 101     Unary - Code Golf     Blowing Fuse     Battleship     Rock Paper Scissors Lizard Spock     TicTacToe     Rock-Paper-Scissors War     Sudoku Validator     7-segment scanner     Flip The Sign     Nuggets numbers     Nature of triangles     if then else     Is the King In Check? (Part 1)     Fractal Image Recognition     Custom Game of Life     Is the King In Check? (Part 2)     Simple AI duels    
Constraint Propagation 2 River Crossing     Wave Function Collapse (sans Shannon)    
Convolution 1 Feature Extraction    
Coop Game 2 Code a la Mode     Fireworks    
Coordinates INTERMEDIATE 4 Divine!     Cloudy Weather     Connect the Hyper-Dots     The Mystic Rectangle    
Counting sort 1 Assignments are boring    
Cryptography ADVANCED 15 Nintendo Sponsored Contest     Anagrams     The Empire Enigma     Encryption/Decryption of Enigma Machine     Enigma - 3 rotors without plugboard     Straddling Checkerboard Cryptography     Her Majesty's well shared secret     Elliptic curve cryptography     Discrete Log Problem     Hacking at RobberCity     Playfair Cipher     Decode the message     SHA-256 Hash     Folding a Note     Detective Geek    
cube 2 Detective Pikaptcha EP4     Die Handedness    
Cycle detection ADVANCED 3 Symbolic system of equations     Bulgarian solitaire     Kaprekar's routine    
Data compression 1 IPv6 Shortener    
Data Structure 1 Container Terminal    
Data Types FUNDAMENTALS 3 Happy Numbers     Unit Fractions     Parse SQL Queries    
DataBases 1 Parse SQL Queries    
decoder INTERMEDIATE 1 Prefix code    
Decryption 0
Dependency Graph INTERMEDIATE 1 1D Spreadsheet    
Depth first search ADVANCED 1 Longest Road    
Determinant 1 Die Handedness    
DFA 0
DFS ADVANCED 7 The Bridge     Vox Codei - Episode 1     Vox Codei - Episode 2     Smash The Code     Hypersonic     orDer oF succeSsion     Locked in gear    
Digit counts FUNDAMENTALS 1 Fair Numbering    
Dijkstra's algorithm 0
DIMACS ADVANCED 1 Horn-SAT solver    
Diophantine Equation ADVANCED 1 Hooch Clash    
Disappointment 1 TryAngle Catch    
Distances INTERMEDIATE 19 Game of Drones     Defibrillators     Mars Lander - Episode 2     Network Cabling     TAN Network     Mars Lander - Episode 3     Poker Chip Race     Mars Lander     Time Travelers     Code vs Zombies     Mad Pod Racing     Soul Snatchers     Broomstick Flyers     Galleon Wars     Spring Challenge 2020     Escaping the cat     🏐 🏖 Beach Volleyball 🏐 🏖     Connect the Hyper-Dots     The Mystic Rectangle    
domino 1 Domino Puzzle    
Dot product INTERMEDIATE 2 Dead men's shot     Feature Extraction    
Double-and-add 1 Elliptic curve cryptography    
Dynamic programming ADVANCED 21 Roller Coaster     Blunder - Episode 2     The Resistance     Ticket to Ride: Europe     Parsing context-free grammar     Max Rect     The Grand Festival - I     The Grand Festival - II     Number of paths between 2 points     2-player game on a calculator     The Balanced Centrifuge Problem     Goro Want Chocolate     Seam Carving     Robbery optimisation     Big Bang Theory - Sheldon's Array Puzzle     Chained Matrix Products     3×N Tiling     Thomas and the Freight Cars     Rod cutting problem     Ways to make change     Prime Fractals in Pascal's Triangle    
Elliptic Curve ADVANCED 1 Elliptic curve cryptography    
Encoding INTERMEDIATE 12 Unary     The Resistance     Music Scores     Bruce Lee     Disordered First Contact     Encryption/Decryption of Enigma Machine     Unary - Code Golf     Decode the message     Byte pair encoding     Bijective Numeration     Substitution Encoding     Code Breaker Puzzle    
Encryption 0
Error-correcting code 1 Extended Hamming Codes    
Exhaustive search INTERMEDIATE 0
Factoring INTERMEDIATE 0
Fermat primes ADVANCED 1 Regular polygons    
Fifteen puzzle 1 Knights Jam    
Flood fill ADVANCED 14 Line Racing     Surface     Time Travelers     Smash The Code     Amazonial     Flood fill Example     Code of Kutulu     Vindinium     Go competition     Coders of the Realm - 1v1     Coders of the Realm     A Game of Go     SameGame     5D Chests    
Formulas FUNDAMENTALS 1 Dolbear's Law    
Fractal 2 What's so complex about Mandelbrot?     Paper-folding curve    
Fruit 2 Smooth!     Smooth Factory    
Game theory 1 Simple AI duels    
Gauss–Wantzel theorem ADVANCED 1 Regular polygons    
Genetic Algorithm ADVANCED 2 Bit Runner 2048     Search Race    
Genetics ADVANCED 1 Blood Types    
Geolocation INTERMEDIATE 1 Hello, World!    
Geometry INTERMEDIATE 16 Nature of quadrilaterals     Apple tree     Morellet’s random lines     1×1×1 Rubik’s cube movements     Counting Squares on Pegs     Darts     Dead men's shot     Smile! Frieze! Cheese!     Encounter surface     The lost files     Flower beds     Low Resolution: What's The Shape?     Nature of triangles     Connect the Hyper-Dots     Die Handedness     Walk on a Die    
Gradient descent 1 Particle Detection with Cloud Chamber    
Graph theory INTERMEDIATE 4 Cross the lines     Plague, Jr     Map Colorations     The lost files    
graph traversal INTERMEDIATE 5 Domino Puzzle     Binary Search Tree Traversal     The lost files     Fall Challenge 2020     We're going in circles!    
Graphs INTERMEDIATE 25 Death First Search - Episode 1     Dwarfs standing on the shoulders of giants     Death First Search - Episode 2     TAN Network     2.5D maze     Cyborg Uprising     The Travelling Salesman Problem     Plight Of The Fellowship Of The Ring     Paper labyrinth     Symbolic system of equations     orDer oF succeSsion     Locked in gear     Mars Colonization     Propositions in Frege’s ideography     Battle Tower     English length units conversion     When pigs fly     Logically reasonable inequalities     Tree Paths     Nurikabe     TryAngle Catch     Spring Challenge 2021     Train passenger     Catching Up     DAWG    
Great-circle distance ADVANCED 1 Hello, World!    
Greedy algorithms INTERMEDIATE 13 The Gift     Super Computer     Magic stones     The Travelling Salesman Problem     Add'em Up     Brick in the Wall     Rearrange string to two numbers     Forest Fire     Huffman Code     Battle Tower     Breaking Apart     Maximising integers     Catching Up    
Grid 4 Flower beds     Kakuro Solver     Is the King In Check? (Part 1)     Is the King In Check? (Part 2)    
Group theory ADVANCED 4 2×2×2 Rubik’s cube movements     Doubly solved Rubik's cube     Ring the bells     Mathematics for big ears    
Guessing digits 1 Guessing digits    
Hash tables FUNDAMENTALS 1 MIME Type    
Hashing 1 SHA-256 Hash    
Heuristic search INTERMEDIATE 1 A-star exercise    
Hooch 1 Hooch Clash    
Horn-SAT ADVANCED 1 Horn-SAT solver    
if/else 1 FireControl    
Image processing ADVANCED 6 Music Scores     Seam Carving     Photo Booth Transformation     Hidden Messages In Images     Fractal Image Recognition     Simple Blur    
Interpolation INTERMEDIATE 1 Her Majesty's well shared secret    
interpreter 4 Reverse Polish Notation     Micro Assembly     Simple CPU Emulation 1     What the Brainfuck !    
Intervals FUNDAMENTALS 4 Shadows of the Knight - Episode 1     Shadows of the Knight - Episode 2     Fair Numbering     Graffiti on the fence    
Jump Point Search INTERMEDIATE 2 Jump Point Search - Preprocessing     Jump Point Search - Runtime    
Lazy Evaluation INTERMEDIATE 1 1D Spreadsheet    
Least-squares 1 Particle Detection with Cloud Chamber    
Lexicographic order 1 Ring the bells    
Line breaks 1 Breaking Apart    
Linear algebra 2 1000000000D WORLD     Die Handedness    
Lists FUNDAMENTALS 11 There is no Spoon - Episode 1     The Urinal Problem     Elementary cellular automaton     Queneau Numbers     2×2×2 Rubik’s cube movements     Criminal     Target Firing     Custom Game of Life     Simple Blur     Wine from Kalbodia - Episode 1     FireControl    
Lizard 0
Logic FUNDAMENTALS 12 Horn-SAT solver     Guessing n Cheating     Guessing digits     Breach     Propositions in Frege’s ideography     Murder in the village!     Find the liars     When pigs fly     Nurikabe     Master of Mayhem     Someone's Acting Sus....     The Hidden Fortress    
Logical problem INTERMEDIATE 1 Assignments are boring    
Loops FUNDAMENTALS 61 Temperatures     ASCII Art     Unary     MIME Type     Defibrillators     Horse-racing Duals     Stock Exchange Losses     Network Cabling     Scrabble     Temperatures     The Descent     May the Triforce be with you!     Rugby score     Reversed Look-and-say     Horse-racing Hyperduals     Folding Paper     Porcupine Fever     Bingo!     Simplified Monopoly™ Turns Prediction     Bank Robbers     Bulgarian solitaire     Brackets, Extended Edition     Ghost Legs     Kaprekar's routine     Pirate's treasure     Rooks Movements     IP mask calculating     Unary - Code Golf     Lumen     Forest Fire     Happy Numbers     Surakarta     Rectangle Partition     Chess board analyzer     Target Firing     Dungeons and Maps     7-segment scanner     Unique Prefixes     Low Resolution: What's The Shape?     Hidden Messages In Images     Ways to make change     🏐 🏖 Beach Volleyball 🏐 🏖     IPv6 Shortener     if then else     Divisibility of Fibonacci numbers sum     Fractal Image Recognition     Pedestrian Traffic     Valid brackets in code     Custom Game of Life     Zhiwei Sun Squares     Shadow Casting     Object Insertion     Folding a Note     Someone's Acting Sus....     Detective Geek     Simple auto-scaling     Lost astronaut     Code Breaker Puzzle     Various Number Spirals     Thermal Flying - Episode 1     FireControl    
Machine learning ADVANCED 3 Basic Decision Tree - 1     Basic Decision Tree - 2     Sticky Keyboard    
Mathematics INTERMEDIATE 35 Quaternion Multiplication     Nature of quadrilaterals     Factorial vs Exponential     Number of letters in a number - Binary     Next car license plate ?     Folding Paper     Execution Circle     What's so complex about Mandelbrot?     Magic count of numbers     Box of Cigars     Expand the polynomial     Morellet’s random lines     Bag of Balls     Bank Robbers     Trits (Balanced Ternary Computing)     Digit sum successor     Her Majesty's well shared secret     Brick in the Wall     Robbery optimisation     Photo Booth Transformation     Bit count to limit     Halting sequences     Smile! Frieze! Cheese!     Encounter surface     Number derivation     Place the Parenthesis     Nature of triangles     Christmas Tree     Prime Fractals in Pascal's Triangle     Zhiwei Sun Squares     Cosmic Love     Primitive Pythagorean Triples     Die Handedness     Walk on a Die     A Bunny and Carrots    
Maths 0
Matrix product INTERMEDIATE 1 Chained Matrix Products    
maze ADVANCED 7 Detective Pikaptcha EP1     Detective Pikaptcha EP2     Detective Pikaptcha EP3     Detective Pikaptcha EP4     Space Maze     Sokoban     Dungeon 3D    
MCTS 1 Night Of War    
Medians INTERMEDIATE 1 Network Cabling    
Memoization ADVANCED 10 Dwarfs standing on the shoulders of giants     Surface     Blunder - Episode 2     The Resistance     Length of Syracuse Conjecture Sequence     1D Spreadsheet     Windmill problem     Van Eck's sequence     Rod cutting problem     Prime Fractals in Pascal's Triangle    
Merge sort 1 1000000000D WORLD    
Minimax ADVANCED 29 Line Racing     Great escape     Amazonial     Minimax exercise     Ultimate Tic-Tac-Toe     Xmas Rush     Vindinium     Yavalath     Cultist Wars     Breakthrough     Paper soccer     Onitama     Tulips and Daisies     Yinsh     Othello     Atari Go     Dots and Boxes     Atari Go 9x9     Blocking     Connect 4     Clobber     Night Of War     Spring Challenge 2021     Amazons     Adversarial Mate with Rook     Abalone     Counting TicTacToe     Lines Of Action     nine men's morris    
Mobius 1 Detective Pikaptcha EP3    
Modular calculus INTERMEDIATE 7 Vortex     Monthly System     Elliptic curve cryptography     Discrete Log Problem     Decode the message     Divisibility of Fibonacci numbers sum     Cooking passion    
Moebius 1 Detective Pikaptcha EP3    
Monte Carlo tree search ADVANCED 16 Monte Carlo Tree Search exercise     Ultimate Tic-Tac-Toe     Langton s Ant     Yavalath     Breakthrough     Tulips and Daisies     Yinsh     Othello     Blocking     Fall Challenge 2020     Clobber     Amazons     Can you save the forest - Episode 1     Abalone     Counting TicTacToe     Lines Of Action    
Multi-agent ADVANCED 13 Platinum Rift - Episode 1     Platinum Rift - Episode 2     Mad Pod Racing     Soul Snatchers     Broomstick Flyers     Galleon Wars     Mean Max     Botters of the Galaxy     Crystal Rush     Spring Challenge 2020     TryAngle Catch     Can you save the forest - Episode 2     Clash of Bots    
neighbour count INTERMEDIATE 1 Detective Pikaptcha EP1    
Neural network ADVANCED 4 Mad Pod Racing     Binary neural network - Part 1     Abalone     Lines Of Action    
NGR 1 1. NGR - Basic Radar    
Nim game 1 Find the winning strategy    
NRPA 1 SameGame    
number system 1 Lost astronaut    
Number theory INTERMEDIATE 8 Hooch Clash     Are The Clumps Normal     Smooth!     Smooth Factory     Unit Fractions     Bailey–Borwein–Plouffe Pi     Primitive Pythagorean Triples     Solid Integer    
Numbers FUNDAMENTALS 1 Next growing number    
Opening Book 1 Yavalath    
Optimization INTERMEDIATE 11 Brain Fork     Code vs Zombies     Mad Pod Racing     Ticket to Ride: Europe     Harmless Rooks     A*Craft     Bender - Episode 4     Road Trip     Big Bang Theory - Sheldon's Array Puzzle     Chained Matrix Products     The Michelangelo Code    
Output formatting FUNDAMENTALS 1 Expand the polynomial    
Palindrome INTERMEDIATE 2 Near-Palindromes     Longest Palindrome    
Parsing FUNDAMENTALS 22 CGX Formatter     XML MDF-2016     Quaternion Multiplication     Brackets, Enhanced Edition     Order of Oopserations!     Numeral system     Expand the polynomial     Trits (Balanced Ternary Computing)     Breach     Fun with Set theory     Propositions in Frege’s ideography     Auto pickup     Source Code Analyser     When pigs fly     Equivalent Resistance, Circuit Building     Place the Parenthesis     IPv6 Shortener     Parse SQL Queries     Bijective Numeration     Offset Arrays     Wine from Kalbodia - Episode 1     Thermal Flying - Episode 1    
Path finding ADVANCED 0
Pathfinding ADVANCED 37 Line Racing     Death First Search - Episode 2     The Labyrinth     Power of Thor - Episode 2     TAN Network     Blunder - Episode 2     The Fall - Episode 2     The Fall - Episode 3     Platinum Rift - Episode 1     Don't Panic - Episode 2     Platinum Rift - Episode 2     Great escape     2.5D maze     Galleon Wars     A-star exercise     Plight Of The Fellowship Of The Ring     Paper labyrinth     orDer oF succeSsion     Number of paths between 2 points     Xmas Rush     Bender - Episode 4     11-puzzle     Cloudy Weather     Paper soccer     Space Maze     Spring Challenge 2020     The lost child.Episode-1     Dungeons and Maps     Jump Point Search - Preprocessing     Sokoban     Jump Point Search - Runtime     Nurikabe     A Man with a Plan     Volcanoes     Train passenger     Dungeon 3D     Catching Up    
Pathfinding, Graphs ADVANCED 0
Patience 1 🃏 FreeCell 🃏    
Pattern recognition ADVANCED 9 Music Scores     Vox Codei - Episode 2     Brain Fork     Divine!     Find the replacement     Trits (Balanced Ternary Computing)     Barcode scanner     Breach     Smile! Frieze! Cheese!    
Permutations INTERMEDIATE 10 Genome Sequencing     Queneau Numbers     Photo Booth Transformation     Crossword     Doubly solved Rubik's cube     Kids Blocks     Ring the bells     Mathematics for big ears     Balanced Levers     Walk on a Die    
Physics INTERMEDIATE 12 Gravity Tumbler     Cards castle     Sandpile addition     Apple tree     Stall tilt     Particle Detection with Cloud Chamber     Equivalent Resistance, Circuit Building     🏐 🏖 Beach Volleyball 🏐 🏖     Cosmic Love     Space Shooter     Balanced Levers     Snooker Ball Collision    
Pi 1 Bailey–Borwein–Plouffe Pi    
Polynomials ADVANCED 1 Her Majesty's well shared secret    
pong 0
Primes INTERMEDIATE 5 Divide the factorial     Count of Primes in a number grid     Factorials of primes decomposition     The Balanced Centrifuge Problem     CGFunge Prime    
Priority Queue INTERMEDIATE 1 Identifying data structure    
Probability INTERMEDIATE 3 Bag of Balls     Dice probability calculator     Benford's law    
Queue FUNDAMENTALS 1 Identifying data structure    
Queues FUNDAMENTALS 1 War    
Radix INTERMEDIATE 3 Mayan Calculation     Numeral system     Bijective Numeration    
Random number generator 1 Simple AI duels    
Range 0
Rational Numbers INTERMEDIATE 1 Rational Number Tree    
Ray Casting 1 Let's make a cheap ASCII 3D engine!    
Reading Comprehension 1 A Man with a Plan    
Reading the statement 5 Hooch Clash     Smooth!     Smooth Factory     In Stereo     Wave Function Collapse (sans Shannon)    
Recursion FUNDAMENTALS 17 Dwarfs standing on the shoulders of giants     Surface     Blunder - Episode 2     The Resistance     There is no Spoon - Episode 2     Carmichael numbers     Winamax Sponsored Contest     2048 scores     The Grand Festival - I     The Grand Festival - II     Go competition     Surakarta     Let's Go To The Cinema!     Divisibility of Fibonacci numbers sum     Offset Arrays     Prime Fractals in Pascal's Triangle     Balanced Levers    
Regression analysis ADVANCED 1 Blunder - Episode 3    
Regular expressions INTERMEDIATE 4 Murder in the village!     IPv6 Shortener     Valid brackets in code     Where's Wally    
Remainder Theorem ADVANCED 1 Remainder Fantasy    
Resource management ADVANCED 8 Game of Drones     Platinum Rift - Episode 1     Platinum Rift - Episode 2     Soul Snatchers     Cyborg Uprising     Code Royale     Tower Dereference     Crystal Rush    
Reverse engineering FUNDAMENTALS 2 CodinGame Sponsored Contest     Breach    
Reverse Polish Notation INTERMEDIATE 2 Reverse Polish Notation     The Polish Dictionary    
Rewriting FUNDAMENTALS 1 Symbolic system of equations    
Rock Paper Scissors 1 Rock-Paper-Scissors War    
rotation INTERMEDIATE 1 Windmill problem    
Rubik's cube 2 2×2×2 Rubik’s cube movements     Doubly solved Rubik's cube    
Rubik’s cube 0
Run-length encoding 1 Binary image    
Satisfiability INTERMEDIATE 1 Horn-SAT solver    
Scheduling ADVANCED 2 Super Computer     Legendary Archer Octavius    
Secret sharing 1 Her Majesty's well shared secret    
Sequences FUNDAMENTALS 4 Conway Sequence     Box of Cigars     Length of Syracuse Conjecture Sequence     Remaining Card    
Set theory FUNDAMENTALS 1 Fun with Set theory    
Sets FUNDAMENTALS 2 Telephone Numbers     Guessing n Cheating    
Sexagesimal system INTERMEDIATE 1 Hello, World!    
SHA-256 1 SHA-256 Hash    
Shortest path ADVANCED 0
Shortest path algorithm 0
Shortest path problem 1 Catching Up    
Simulated Annealing ADVANCED 1 Search Race    
Simulation INTERMEDIATE 31 Blunder - Episode 1     Roller Coaster     Poker Chip Race     Vox Codei - Episode 1     Vox Codei - Episode 2     Time Travelers     Code vs Zombies     Smash The Code     Hypersonic     Broomstick Flyers     Amazonial     Mean Max     A*Craft     Bit Runner 2048     Detective Pikaptcha EP2     Detective Pikaptcha EP3     Detective Pikaptcha EP4     Let's Go To The Cinema!     Space Maze     Tower Dereference     TicTacToe     Search Race     SameGame     2048     Volcanoes     Custom Game of Life     Can you save the forest - Episode 1     Can you save the forest - Episode 2     Space Shooter     Snooker Ball Collision     Thermal Flying - Episode 1    
Sliding window 1 Feature Extraction    
Smooth 2 Smooth!     Smooth Factory    
Snell's Law 1 🏐 🏖 Beach Volleyball 🏐 🏖    
Sorting FUNDAMENTALS 6 Add'em Up     Dynamic sorting     Hunger Games     Thomas and the Freight Cars     Inversion count     Magic String    
Spock 0
SQL 1 Parse SQL Queries    
Stack FUNDAMENTALS 8 Reverse Polish Notation     Micro Assembly     Simple CPU Emulation 1     Identifying data structure     Let's Go To The Cinema!     The Polish Dictionary     Container Terminal     Valid brackets in code    
State machine ADVANCED 10 Blunder - Episode 1     Soul Snatchers     Elementary cellular automaton     Langton's ant     Parsing context-free grammar     Code4Life     Code a la Mode     Is that a possible word? EP1     Fireworks     Simple AI duels    
steganography 1 Hidden Messages In Images    
Steiner Tree 1 Binary Extension    
Streams FUNDAMENTALS 1 Smooth Factory    
string FUNDAMENTALS 2 Unary - Code Golf     Detective Geek    
String manipulation FUNDAMENTALS 29 Text alignment     Anagrams     Army ants     Reversed Look-and-say     Bulk Email Generator     Organic Compounds 🔬     Encryption/Decryption of Enigma Machine     Rectangular block spinner     Dynamic sorting     Fishing With A Stick     Rearrange string to two numbers     Create the longest sequence of 1s     TicTacToe     Auto pickup     Source Code Analyser     Breaking Apart     7-segment scanner     Prefix code     Unique Prefixes     Nicholas Breakspeare and Hugh of Evesham     Place the Parenthesis     if then else     Valid brackets in code     In Stereo     Substitution Encoding     Caesar is the chief     Cooking passion     Where's Wally     Magic String    
Strings FUNDAMENTALS 35 ASCII Art     Unary     MIME Type     Mayan Calculation     CGX Formatter     Genome Sequencing     Othello     XML MDF-2016     Jack Silver: The Casino     How time flies     Nature of quadrilaterals     2×2×2 Rubik’s cube movements     Hidden word     Longest Palindrome     Monthly System     Paper-folding curve     Text formatting     Find the replacement     Paper labyrinth     De-FizzBuzzer     Encryption/Decryption of Enigma Machine     Fishing With A Stick     Criminal     Palindromic Decomposition     Breach     Crossword     Chess board analyzer     Dungeons and Maps     Particle Detection with Cloud Chamber     IPv6 Shortener     Master of Mayhem     The Michelangelo Code     In Stereo     Substitution Encoding     FireControl    
Strive for Simplicity 1 Robot Show    
Tables 1 Parse SQL Queries    
Tile-matching 1 SameGame    
Tiling 2 Depot organization     3×N Tiling    
Time 2 🏐 🏖 Beach Volleyball 🏐 🏖     Railway Station Clock    
Topology INTERMEDIATE 3 Cross the lines     HTML table cell split     The lost files    
Transformations 1 Smile! Frieze! Cheese!    
Trees INTERMEDIATE 5 Ancestors & Descendants     Code your own Automaton2000, step 1     Plague, Jr     Huffman Code     Find the liars    
Tricky 1 Sum of divisors    
Tries ADVANCED 2 Telephone Numbers     Prefix code    
Trigonometry INTERMEDIATE 12 Defibrillators     Mars Lander - Episode 2     TAN Network     Mars Lander - Episode 3     Mars Lander     Mad Pod Racing     Nature of quadrilaterals     Broomstick Flyers     Hello, World!     Escaping the cat     Nature of triangles     Let's make a cheap ASCII 3D engine!    
Two pointers 1 1000000000D WORLD    
UCB1 1 Monte Carlo Tree Search exercise    
UCT 1 Monte Carlo Tree Search exercise    
Unit propagation 2 Horn-SAT solver     English length units conversion    
windmill 1 Windmill problem    
XOR FUNDAMENTALS 1 Hacking at RobberCity    
💡💡💡💡💡 1 Light Bulbs    
💦💦💦🔥🔥🔥 1 1D Bush Fire