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 400th MeWhenI 🇻🇦 876 70 2ms 21 Nov 2025 402nd MeWhenI 🇻🇦 876 75 127ms 23 Nov 2025 402nd Natanaelel 🇸🇪 876 75 123ms 4 Jan 2026 404th MeWhenI 🇻🇦 875 37 2ms 21 Nov 2025 405th primo-ppcg 🇹🇭 875 208 14ms 25 Jan 2026 406th JayXon 🇺🇸 874 119 1,909ms 20 Dec 2025 407th Yax42 🇫🇷 873 81 476ms 9 Jan 2026 408th canissimia 🇦🇶 873 179 33ms 24 Dec 2025 409th rucin93 🇵🇱 872 62 2ms 31 Oct 2025 409th dokutan 872 62 2ms 28 Nov 2025 409th snoozingnewt 🇨🇦 872 62 2ms 24 days ago 409th plcc0 872 62 2ms 22 days ago 413th sean-niemann 🇺🇸 872 88 8ms 18 Dec 2025 414th MeWhenI 🇻🇦 872 89 71ms 21 Nov 2025 415th albanian-laundromat 871 72 83ms 16 Dec 2025 416th emgordon154 871 85 425ms 21 Dec 2025 416th fuzzylojik-golf 🇺🇸 871 85 412ms 19 days ago 418th pardouin 🇫🇷 871 87 26ms 25 Feb 2026 419th MeWhenI 🇻🇦 871 92 25ms 24 Nov 2025 420th targrik 870 51 10ms 30 Oct 2025 420th luuumine 🇫🇷 870 51 11ms 3 Dec 2025 420th emgordon154 870 51 11ms 21 Dec 2025 423rd pardouin 🇫🇷 870 54 4ms 23 days ago 424th stefangimmillaro 870 57 5ms 31 Oct 2025 425th bitsandbeyond 🇳🇱 870 72 41ms 1 Nov 2025 426th snoozingnewt 🇨🇦 870 78 39ms 11 Dec 2025 427th bitsandbeyond 🇳🇱 869 55 442ms 1 Nov 2025 427th Shanethegamer 🇺🇸 869 55 425ms 3 Nov 2025 427th m-tkach 🇺🇦 869 55 472ms 24 Nov 2025 427th ovs-code 🇩🇪 869 55 453ms 28 Nov 2025 427th snoozingnewt 🇨🇦 869 55 390ms 28 Nov 2025 427th fuzzylojik-golf 🇺🇸 869 55 356ms 8 Jan 2026 433rd GolfingSuccess 🇬🇷 869 74 14ms 15 Nov 2025 433rd Steffan153 🇫🇮 869 74 14ms 23 days ago 435th DialFrost 🇸🇬 869 96 282ms 21 Dec 2025 436th KatieLG 🇬🇧 869 98 2ms 1 Dec 2025 437th Shanethegamer 🇺🇸 868 49 364ms 3 Nov 2025 438th KasperKivimaeki 🇫🇮 868 57 11ms 30 Oct 2025 438th Shanethegamer 🇺🇸 868 57 12ms 3 Nov 2025 438th 4atj 868 57 12ms 5 Nov 2025 438th MeWhenI 🇻🇦 868 57 12ms 21 Nov 2025 438th CaedenHarper 🇨🇦 868 57 12ms 29 Nov 2025 438th blaztoma 🇱🇹 868 57 12ms 30 Nov 2025 438th FortuiteMan 🇫🇷 868 57 12ms 30 Nov 2025 438th ryyyn 🇺🇸 868 57 11ms 1 Dec 2025 438th DialFrost 🇸🇬 868 57 12ms 2 Dec 2025 438th fuzzylojik-golf 🇺🇸 868 57 12ms 2 Dec 2025 438th starfihs 868 57 11ms 4 Dec 2025 438th qpwoeirut 868 57 12ms 7 Dec 2025 438th dominikvytisk 868 57 12ms 8 Dec 2025 438th Natanaelel 🇸🇪 868 57 12ms 25 Dec 2025 438th 5cw 🇺🇸 868 57 11ms 20 Feb 2026 438th StefanHabel 🇨🇦 868 57 11ms 11 days ago 454th kg583 🇺🇸 868 83 3ms 6 days ago 455th Yax42 🇫🇷 867 72 504ms 29 Nov 2025 456th MeWhenI 🇻🇦 864 56 914ms 24 Nov 2025 456th plcc0 864 56 750ms 9 days ago 458th madex 🇩🇪 864 76 128ms 11 days ago 459th bitsandbeyond 🇳🇱 863 52 35ms 1 Nov 2025 460th iczelia 🇩🇪 863 71 2ms 1 Dec 2025 461st pardouin 🇫🇷 863 85 62ms 1 Dec 2025 462nd CaedenHarper 🇨🇦 863 90 452ms 29 Nov 2025 462nd BlankSpruce 863 90 67ms 6 Dec 2025 462nd TheSecondComing123 863 90 59ms 24 Feb 2026 465th vhoulbreque 🇫🇷 863 106 8ms 1 Dec 2025 466th bitsandbeyond 🇳🇱 862 82 473ms 3 Jan 2026 467th dokutan 861 78 12ms 1 Dec 2025 468th bitsandbeyond 🇳🇱 861 93 26ms 1 Nov 2025 469th bitsandbeyond 🇳🇱 860 97 295ms 1 Nov 2025 470th jared-hughes 859 63 2ms 23 days ago 471st MeWhenI 🇻🇦 859 79 40ms 23 Nov 2025 472nd albanian-laundromat 859 119 1,459ms 30 Oct 2025 473rd dokutan 857 72 2,665ms 28 Nov 2025 474th bitsandbeyond 🇳🇱 856 53 1,275ms 1 Nov 2025 475th DialFrost 🇸🇬 856 57 2ms 19 Dec 2025 476th fuzzylojik-golf 🇺🇸 855 50 3ms 8 Jan 2026 477th primo-ppcg 🇹🇭 855 58 6ms 24 days ago 477th Seek64 🇩🇪 855 58 5ms 24 days ago 479th MeWhenI 🇻🇦 855 70 112ms 23 Nov 2025 480th Shanethegamer 🇺🇸 855 73 391ms 4 Nov 2025 First Prev 401–480 of 1,462 Next Last