The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 5 days. Why not try and solve them ahead of time?
Tower of Hanoi in all languages in chars. Achievements Cheevos Holes Languages Medals Miscellaneous All Holes 12 Days of Christmas 24 Game 99 Bottles of Beer Abundant Numbers Abundant Numbers (Long) Arabic to Roman Arithmetic Numbers Arrows Ascending Primes ASCII Table Billiards brainfuck Calendar Card Number Validation Catalan Numbers Catalan’s Constant Christmas Trees Collatz Continued Fractions CSS Colors Cubes Day of Week DFA Simulator Diamonds Divisors Emirp Numbers Emirp Numbers (Long) Emojify Evil Numbers Evil Numbers (Long) Factorial Factorisation Farey Sequence Fibonacci Fizz Buzz Foo Fizz Buzz Bar Forsyth–Edwards Notation Fractions Game of Life Gijswijt’s Sequence Happy Numbers Happy Numbers (Long) Hexdump Hilbert Curve Intersection Inventory Sequence ISBN Jacobi Symbol Kaprekar Numbers Kolakoski Constant Kolakoski Sequence Leap Years Levenshtein Distance Leyland Numbers ln 2 Look and Say Lucky Numbers Lucky Tickets Mahjong Mandelbrot Maze Medal Tally Minesweeper Morse Decoder Morse Encoder Multitap Input Musical Chords N Queens Niven Numbers Niven Numbers (Long) Number Spiral Odious Numbers Odious Numbers (Long) Ordinal Numbers PalindromemordnilaP Pangram Grep Partition Numbers Pascal’s Triangle Pernicious Numbers Pernicious Numbers (Long) Poker Polyominoes Prime Numbers Prime Numbers (Long) Proximity Grid QR Decoder Quine Recamán Repeating Decimals Reverse Polish Notation Reversi Rijndael S-box Rock-paper-scissors-Spock-lizard Roman to Arabic ROT13 Rule 110 Scrambled Sort Set Seven Segment SI Units Sierpiński Triangle Smith Numbers Spelling Numbers Star Wars GPT Star Wars Opening Crawl Sudoku Sudoku (Fill-in) Ten-pin Bowling Tic-tac-toe Time Distance Tongue-twisters Topological Sort Tower of Hanoi Transpose Sentence Trinomial Triangle United States Vampire Numbers Van Eck Sequence Zeckendorf Representation Zodiac Signs γ λ π τ φ √2 𝑒 Alphabetic Numbers Apéry’s Constant Binary Lambda Calculus Connect Four Crossword CSS Colors (Inverse) CSS Grid Ellipse Perimeters Flags Floyd-Steinberg Dithering Gray Code Decoder Gray Code Encoder Hexagonal Spiral Highly Composite Numbers NFA Simulator Numbrix Odd Polyomino Tiling p-adic Expansion Polygon Triangulations QR Encoder Quadratic Formula Rectangle Fill Semiprime Numbers Smooth Numbers Snake Sphenic Numbers Taxicab Numbers Turtle Tutorial All Languages ><> ALGOL 68 ArkScript Assembly AWK Bash BASIC Berry brainfuck C C# C++ Civet Clojure COBOL Coconut Common Lisp Crystal D Dart Elixir Erlang F# Factor Forth Fortran Gleam Go GolfScript Groovy Haskell Hexagony J Janet Java JavaScript jq Julia K Kotlin Lua Nim OCaml Pascal Perl PHP PowerShell Prolog Python R Raku Rockstar Ruby Rust Scheme sed SQL Swift Tcl TeX V VimL Wren Zig 05AB1E APL Arturo Befunge BQN CJam CoffeeScript Egel Fennel Harbour Hare Haxe Hush Hy iogii Knight Lily Luau Odin Picat Qore Racket Rebol Rexx Scala Squirrel Stax Uiua Umka Vala Vyxal Bytes Chars Scoring Bytes Chars Language All ><> ALGOL 68 ArkScript Assembly AWK Bash BASIC Berry brainfuck C C# C++ Civet Clojure COBOL Coconut Common Lisp Crystal D Dart Elixir Erlang F# Factor Forth Fortran Gleam Go GolfScript Groovy Haskell Hexagony J Janet Java JavaScript jq Julia K Kotlin Lua Nim OCaml Pascal Perl PHP PowerShell Prolog Python R Raku Rockstar Ruby Rust Scheme sed SQL Swift Tcl TeX V VimL Wren Zig Experimental Language 05AB1E APL Arturo Befunge BQN CJam CoffeeScript Egel Fennel Harbour Hare Haxe Hush Hy iogii Knight Lily Luau Odin Picat Qore Racket Rebol Rexx Scala Squirrel Stax Uiua Umka Vala Vyxal Hole All 12 Days of Christmas 24 Game 99 Bottles of Beer Abundant Numbers Abundant Numbers (Long) Arabic to Roman Arithmetic Numbers Arrows Ascending Primes ASCII Table Billiards brainfuck Calendar Card Number Validation Catalan Numbers Catalan’s Constant Christmas Trees Collatz Continued Fractions CSS Colors Cubes Day of Week DFA Simulator Diamonds Divisors Emirp Numbers Emirp Numbers (Long) Emojify Evil Numbers Evil Numbers (Long) Factorial Factorisation Farey Sequence Fibonacci Fizz Buzz Foo Fizz Buzz Bar Forsyth–Edwards Notation Fractions Game of Life Gijswijt’s Sequence Happy Numbers Happy Numbers (Long) Hexdump Hilbert Curve Intersection Inventory Sequence ISBN Jacobi Symbol Kaprekar Numbers Kolakoski Constant Kolakoski Sequence Leap Years Levenshtein Distance Leyland Numbers ln 2 Look and Say Lucky Numbers Lucky Tickets Mahjong Mandelbrot Maze Medal Tally Minesweeper Morse Decoder Morse Encoder Multitap Input Musical Chords N Queens Niven Numbers Niven Numbers (Long) Number Spiral Odious Numbers Odious Numbers (Long) Ordinal Numbers PalindromemordnilaP Pangram Grep Partition Numbers Pascal’s Triangle Pernicious Numbers Pernicious Numbers (Long) Poker Polyominoes Prime Numbers Prime Numbers (Long) Proximity Grid QR Decoder Quine Recamán Repeating Decimals Reverse Polish Notation Reversi Rijndael S-box Rock-paper-scissors-Spock-lizard Roman to Arabic ROT13 Rule 110 Scrambled Sort Set Seven Segment SI Units Sierpiński Triangle Smith Numbers Spelling Numbers Star Wars GPT Star Wars Opening Crawl Sudoku Sudoku (Fill-in) Ten-pin Bowling Tic-tac-toe Time Distance Tongue-twisters Topological Sort Tower of Hanoi Transpose Sentence Trinomial Triangle United States Vampire Numbers Van Eck Sequence Zeckendorf Representation Zodiac Signs γ λ π τ φ √2 𝑒 Experimental Hole Alphabetic Numbers Apéry’s Constant Binary Lambda Calculus Connect Four Crossword CSS Colors (Inverse) CSS Grid Ellipse Perimeters Flags Floyd-Steinberg Dithering Gray Code Decoder Gray Code Encoder Hexagonal Spiral Highly Composite Numbers NFA Simulator Numbrix Odd Polyomino Tiling p-adic Expansion Polygon Triangulations QR Encoder Quadratic Formula Rectangle Fill Semiprime Numbers Smooth Numbers Snake Sphenic Numbers Taxicab Numbers Turtle Tutorial # Golfer Points Chars Time Submitted 239th Natanaelel 🇸🇪 907 46 92ms 23 days ago 239th edsrzf 🇳🇿 907 46 119ms 14 days ago 243rd bitsandbeyond 🇳🇱 907 66 103ms 2 Nov 2025 243rd stefangimmillaro 907 66 108ms 4 Nov 2025 243rd edsrzf 🇳🇿 907 66 7ms 16 days ago 243rd edsrzf 🇳🇿 907 66 109ms 5 days ago 247th jkelly467 907 68 2,517ms 1 Dec 2025 247th fuzzylojik-golf 🇺🇸 907 68 2,459ms 2 hours ago 249th kg583 🇺🇸 907 74 11ms 30 Oct 2025 250th GolfingSuccess 🇬🇷 907 92 311ms 30 Oct 2025 250th edsrzf 🇳🇿 907 92 298ms 31 Oct 2025 250th KasperKivimaeki 🇫🇮 907 92 306ms 31 Oct 2025 253rd Natanaelel 🇸🇪 906 32 43ms 25 Dec 2025 253rd CaedenHarper 🇨🇦 906 32 41ms 23 days ago 255th CaedenHarper 🇨🇦 906 78 448ms 29 Nov 2025 255th m-tkach 🇺🇦 906 78 511ms 1 Dec 2025 257th emgordon154 905 67 5ms 23 Nov 2025 258th sean-niemann 🇺🇸 905 69 405ms 31 Oct 2025 258th stefangimmillaro 905 69 419ms 31 Oct 2025 258th GolfingSuccess 🇬🇷 905 69 447ms 31 Oct 2025 258th AdrienHache 🇫🇷 905 69 425ms 1 Nov 2025 258th pardouin 🇫🇷 905 69 509ms 29 Nov 2025 258th DialFrost 🇸🇬 905 69 405ms 2 Dec 2025 258th KasperKivimaeki 🇫🇮 905 69 409ms 2 Dec 2025 258th JayXon 🇺🇸 905 69 416ms 20 Dec 2025 258th nwellnhof 🇩🇪 905 69 400ms 31 Dec 2025 258th namelessiw 905 69 426ms 1 Jan 2026 258th Steffan153 🇫🇮 905 69 434ms 24 days ago 258th fuzzylojik-golf 🇺🇸 905 69 435ms 18 days ago 270th stefangimmillaro 905 75 41ms 31 Oct 2025 271st emgordon154 905 87 124ms 4 Dec 2025 272nd MeWhenI 🇻🇦 903 53 2ms 23 Nov 2025 273rd Shanethegamer 🇺🇸 903 84 28ms 2 Nov 2025 273rd m-tkach 🇺🇦 903 84 26ms 1 Dec 2025 275th luuumine 🇫🇷 903 86 59ms 11 Dec 2025 276th emgordon154 902 53 421ms 20 Dec 2025 276th plcc0 902 53 357ms 22 days ago 278th bitsandbeyond 🇳🇱 902 60 2ms 2 Nov 2025 278th Shanethegamer 🇺🇸 902 60 2ms 3 Nov 2025 278th MeWhenI 🇻🇦 902 60 2ms 24 Nov 2025 278th FlyingPenguin223 902 60 2ms 3 Dec 2025 278th CornerMercury 🇬🇧 902 60 2ms 24 days ago 283rd edsrzf 🇳🇿 902 85 8ms 5 days ago 284th saito-ta 🇯🇵 901 51 583ms 31 Oct 2025 284th MeWhenI 🇻🇦 901 51 542ms 29 Nov 2025 284th kritixilithos 901 51 536ms 18 days ago 287th rucin93 🇵🇱 901 55 6ms 30 Oct 2025 287th fuzzylojik-golf 🇺🇸 901 55 6ms 15 days ago 289th CaedenHarper 🇨🇦 901 68 2ms 29 Nov 2025 289th m-tkach 🇺🇦 901 68 2ms 1 Dec 2025 291st sean-niemann 🇺🇸 900 66 4ms 18 Dec 2025 292nd sean-niemann 🇺🇸 900 89 26ms 2 Dec 2025 293rd stefangimmillaro 899 55 12ms 30 Oct 2025 293rd bricknellj 899 55 12ms 30 Oct 2025 293rd ovs-code 🇩🇪 899 55 12ms 31 Oct 2025 293rd bitsandbeyond 🇳🇱 899 55 12ms 1 Nov 2025 293rd GolfingSuccess 🇬🇷 899 55 11ms 3 Nov 2025 293rd Mukundan314 899 55 13ms 15 Nov 2025 293rd m-tkach 🇺🇦 899 55 12ms 24 Nov 2025 293rd snoozingnewt 🇨🇦 899 55 11ms 28 Nov 2025 293rd luuumine 🇫🇷 899 55 11ms 28 Nov 2025 293rd dokutan 899 55 12ms 1 Dec 2025 293rd xsot 🇸🇬 899 55 11ms 2 Dec 2025 293rd vhoulbreque 🇫🇷 899 55 12ms 2 Dec 2025 293rd jared-hughes 899 55 12ms 3 Dec 2025 293rd duckyluuk 🇳🇱 899 55 11ms 4 Dec 2025 293rd GrayJoKing 🇦🇺 899 55 12ms 5 Dec 2025 293rd enigma 899 55 12ms 20 Dec 2025 293rd taifu 899 55 24ms 21 Dec 2025 293rd jatloe 899 55 12ms 20 Jan 2026 293rd Lv0Sys 🇵🇱 899 55 12ms 21 Feb 2026 293rd edsrzf 🇳🇿 899 55 11ms 5 days ago 313th DialFrost 🇸🇬 899 71 15ms 22 Dec 2025 314th ovs-code 🇩🇪 898 50 34ms 28 Nov 2025 314th sean-niemann 🇺🇸 898 50 43ms 1 Dec 2025 314th nwellnhof 🇩🇪 898 50 36ms 1 Jan 2026 314th error256 898 50 38ms 24 days ago 314th Steffan153 🇫🇮 898 50 38ms 23 days ago 319th m-tkach 🇺🇦 897 95 2ms 1 Dec 2025 320th CaedenHarper 🇨🇦 896 54 786ms 30 Nov 2025 First Prev 241–320 of 1,462 Next Last