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?
12 Days of Christmas 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 638th M450NCH00 369 517 9ms 4 Feb 2023 638th resoNathan 369 517 10ms 8 Jul 2024 638th IoLimmer 369 517 9ms 11 Jul 2024 638th Brokames 369 517 10ms 6 Jun 2025 645th Daniel-Martin576 369 518 10ms 1 Apr 2020 645th andrewgopher 369 518 9ms 28 Jul 2021 645th dlee888 369 518 10ms 17 Nov 2023 645th karadigm01 369 518 10ms 23 days ago 649th GodEmperorCaterpie 368 519 10ms 5 Sep 2019 649th lemogne 368 519 10ms 9 Aug 2021 649th ToE42 368 519 11ms 7 Sep 2021 649th 104210 368 519 9ms 9 Nov 2022 649th tmanternach 368 519 10ms 23 Nov 2022 649th marcus-gomes-v 🇧🇷 368 519 11ms 23 Feb 2025 649th bradye31 368 519 10ms 20 Nov 2025 649th kayaulai 368 519 10ms 23 Nov 2025 657th Stockoh 🇫🇷 367 520 9ms 11 May 2021 657th Kasci 367 520 10ms 28 Dec 2021 657th azure-blondon 367 520 10ms 25 Dec 2023 657th joao-parreira 367 520 31ms 24 Apr 2024 657th kejcao 🇨🇦 367 520 16ms 10 May 2024 657th Florian-Mt 367 520 9ms 4 Dec 2025 663rd mothcolada 🇺🇸 367 521 11ms 11 Mar 2021 663rd nikhil9302 367 521 10ms 21 Nov 2021 663rd LeeCamp 367 521 10ms 11 Dec 2021 663rd jhpaques 🇫🇷 367 521 10ms 28 Dec 2022 663rd WillConker 367 521 11ms 14 Jul 2023 663rd 0xkarambit 367 521 10ms 27 days ago 669th HemangRajvanshy 366 522 10ms 1 Apr 2020 669th nmgetahun 366 522 10ms 5 Dec 2022 669th pde-bakk 🇳🇱 366 522 10ms 21 Oct 2023 669th raflemakt 366 522 10ms 3 Jan 2024 669th codingisgreatbutiamnot 366 522 10ms 29 Jul 2024 669th Kowalskiexe 🇵🇱 366 522 10ms 19 Apr 2025 675th nickrodgers42 365 523 10ms 2 Oct 2020 675th piebot3000 365 523 10ms 13 Sep 2023 675th IdkWhatIsIdk 365 523 10ms 28 Oct 2024 675th OyuDays 365 523 10ms 17 Mar 2025 675th AdamMorris377 365 523 10ms 1 Jan 2026 675th jusaka 365 523 10ms 5 days ago 681st gardarjuto 365 524 10ms 16 Nov 2020 681st xy3 🇮🇪 365 524 10ms 4 Jan 2022 681st xenufo 365 524 10ms 14 Jul 2022 681st james-downey 365 524 10ms 14 Jul 2022 681st Argon1999 365 524 10ms 21 Oct 2022 686th NicoAdams 364 525 10ms 21 Nov 2021 686th sleepyStick 364 525 11ms 5 Apr 2022 686th ce-warren 364 525 10ms 26 Aug 2023 686th qwjhvbxi 364 525 11ms 5 Feb 2024 686th TheAtrossian 364 525 10ms 5 Jan 2025 686th HagenFritz 364 525 10ms 19 Jun 2025 692nd babulibaba 363 526 10ms 15 Aug 2019 692nd ashwinvis 363 526 9ms 17 Apr 2020 692nd hdformat 363 526 10ms 8 Jun 2020 692nd mathwiz42 363 526 10ms 17 Aug 2020 692nd confy 363 526 12ms 25 Oct 2020 692nd dgambit 363 526 10ms 2 Apr 2021 692nd goldstraw 363 526 10ms 30 Nov 2021 692nd JohannaWarnqvist 363 526 10ms 13 Feb 2022 692nd martinnorling 🇸🇪 363 526 10ms 28 Feb 2022 692nd ezhereshchin 363 526 11ms 1 May 2022 692nd fredoinsilico 363 526 9ms 7 Sep 2023 692nd aviyanp 363 526 10ms 13 Oct 2025 692nd ethanlchristensen 363 526 10ms 17 Oct 2025 692nd ElieDeBrauwer 363 526 10ms 25 Oct 2025 706th asadullayev 362 527 10ms 8 Jan 2021 706th PYRiTEmonark 362 527 10ms 11 Mar 2021 706th BackslashWelsh 362 527 9ms 23 Jul 2021 706th TyKeeling 362 527 9ms 22 Jun 2022 706th SomeSomeOne99 362 527 10ms 26 Mar 2025 706th asarvazyan 362 527 10ms 22 Oct 2025 712th willzywiec 362 528 31ms 8 Aug 2018 712th ionutm82 362 528 10ms 9 Nov 2018 712th jhunterkohler 362 528 10ms 20 May 2021 712th elephantpanda 362 528 10ms 14 Oct 2022 712th sandorstormen 362 528 10ms 11 Mar 2023 712th fbe 362 528 10ms 11 Sep 2024 712th MasterGodzilla 362 528 16ms 26 Jun 2025 712th themoonisacheese 362 528 9ms 29 Dec 2025 712th Languag3 362 528 10ms 26 Jan 2026 First Prev 641–720 of 1,167 Next Last
