The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 7 days. Why not try and solve them ahead of time?
Arabic to Roman in Python 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 160th NanduBC 500 176 26ms 17 Mar 2021 160th za3k 500 176 23ms 11 Oct 2022 160th msbranicky 500 176 21ms 27 Jul 2023 160th ssbhatt4321 500 176 31ms 14 Oct 2023 160th JorgiEagle 500 176 21ms 8 Feb 2024 160th hiichbindermax 500 176 26ms 11 Sep 2024 167th drochom 497 177 20ms 20 Jun 2024 167th vhoulbreque 🇫🇷 497 177 22ms 13 Sep 2025 167th CaedenHarper 🇨🇦 497 177 43ms 29 Oct 2025 170th Alex-x90 🇺🇸 494 178 47ms 13 Feb 2023 170th snooze92 🇫🇷 494 178 22ms 26 Feb 2025 170th milana-94888u 494 178 20ms 5 Mar 2025 170th InigoK 🇺🇸 494 178 27ms 26 Aug 2025 174th urojony 🇵🇱 492 179 24ms 27 May 2021 174th raspofabs 492 179 24ms 8 Jul 2023 174th FranklinJiaChen 492 179 22ms 12 Jun 2024 174th kistlerf 🇨🇭 492 179 37ms 12 May 2025 174th LuisGoncalves05 🇵🇹 492 179 23ms 11 Jul 2025 174th jacekwladzinski 492 179 35ms 8 Oct 2025 180th Indivicivet 489 180 20ms 11 Mar 2021 180th cesarm4 489 180 26ms 31 Aug 2021 180th idoweinstein 489 180 20ms 5 Aug 2022 180th ellis-rix 489 180 24ms 25 Aug 2022 180th StardustGogeta 489 180 24ms 18 Aug 2023 180th Andrey2001 489 180 27ms 23 Nov 2025 186th nstearns96 🇬🇧 486 181 28ms 29 Nov 2022 186th pde-bakk 🇳🇱 486 181 26ms 23 Oct 2023 186th EnTerr 486 181 24ms 8 Sep 2024 186th Josemnz 486 181 23ms 4 May 2025 190th kevinmchung 484 182 35ms 2 Feb 2018 190th cefqrn 484 182 29ms 20 May 2023 190th fgrosshans 🇫🇷 484 182 22ms 16 Jul 2024 193rd asheeri 481 183 22ms 14 Aug 2021 193rd TaserTheFox 🇺🇸 481 183 24ms 8 May 2023 195th adoxography 478 184 21ms 10 Oct 2019 195th yishayv 478 184 21ms 23 Jan 2023 195th Bmrl7 478 184 27ms 17 Feb 2024 198th DxSper 476 185 34ms 16 Feb 2024 198th OCNeve 476 185 19ms 18 Jun 2024 198th croc54 476 185 21ms 31 Jan 2025 198th Alpha9584 476 185 20ms 20 Mar 2025 198th Hemanthred2005 476 185 25ms 3 May 2025 198th GodlyProgrammer1 476 185 25ms 28 Nov 2025 204th TheAristos 473 186 30ms 21 Oct 2019 204th CorporalCrawdad 473 186 21ms 3 Oct 2024 206th rowboat1 471 187 25ms 3 Apr 2021 206th bogosorter 471 187 43ms 11 Jul 2025 206th robin-scragg 471 187 27ms 27 Jul 2025 206th celiendonze 🇨🇭 471 187 24ms 7 Nov 2025 210th jhfranklin 🇬🇧 468 188 25ms 7 Mar 2021 210th ehulinsky 🇺🇸 468 188 20ms 8 May 2023 210th eiburns 468 188 20ms 3 Oct 2023 210th Just4FunCoder 468 188 40ms 18 Jun 2025 214th ay2718 466 189 29ms 14 Aug 2019 214th Kloppermand 🇩🇰 466 189 21ms 10 Jun 2020 214th martinnorling 🇸🇪 466 189 23ms 3 Mar 2022 214th ThijsLuttikhuis 466 189 28ms 3 Mar 2024 214th Mathrew2012 466 189 17ms 24 May 2025 219th LogicalJoe 463 190 34ms 24 May 2023 219th bwenstar 463 190 24ms 21 Feb 2024 219th moustave 463 190 31ms 7 Apr 2025 222nd garrisonhh 461 191 20ms 21 Nov 2020 222nd geofft 461 191 41ms 10 Dec 2020 222nd CedricGebistorf 461 191 23ms 18 Feb 2022 222nd Educorreia932 461 191 23ms 23 Jun 2022 222nd Ripick 461 191 25ms 6 May 2023 222nd anarconic 461 191 470ms 14 Dec 2023 222nd jeff-re 461 191 22ms 6 May 2025 222nd Troon 461 191 21ms 19 Aug 2025 222nd nemoyatpeace 461 191 26ms 8 Jan 2026 231st hellwue 458 192 22ms 22 Nov 2023 231st ballaire 458 192 40ms 27 Jan 2024 233rd evanrittner 456 193 22ms 9 Mar 2019 233rd argusdusty 🇺🇸 456 193 35ms 31 Dec 2020 233rd Bonjour27891 🇻🇳 456 193 39ms 13 Mar 2022 233rd AtengChen 456 193 23ms 16 Aug 2024 237th Psirving 454 194 24ms 31 Jul 2020 237th j-Ewan 454 194 22ms 14 Feb 2022 237th Dandandooo 454 194 21ms 19 Apr 2025 240th cros107 🇦🇺 451 195 26ms 7 Jun 2023 First Prev 161–240 of 507 Next Last