The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 2 days. Why not try and solve them ahead of time?
12 Days of Christmas in Python in bytes. 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 Bytes Time Submitted 398th AkashTandon167 389 488 11ms 25 Jan 2021 398th Omega65536 🇩🇪 389 488 10ms 23 Jun 2021 398th Sturla22 389 488 11ms 4 Apr 2022 398th HumanoidCPU 389 488 11ms 26 Mar 2024 398th BrunoVisnadi 🇧🇷 389 488 10ms 3 Oct 2025 398th Code-Coder-coder 389 488 9ms 11 Oct 2025 407th jgermain48 389 489 10ms 8 Dec 2019 408th ly0va 388 490 9ms 7 Jan 2019 408th chrismilson 388 490 10ms 18 May 2020 408th Jacob385 388 490 10ms 13 Mar 2024 408th rucin93 🇵🇱 388 490 9ms 26 Jul 2024 408th hippopotam00sehead 🇨🇦 388 490 10ms 16 Sep 2024 408th jbjd 388 490 10ms 17 Sep 2024 408th lelbal 388 490 10ms 19 Sep 2024 408th DraigRygbi 388 490 10ms 19 Dec 2024 408th argentite 388 490 10ms 11 Sep 2025 417th mikelane 387 491 10ms 29 Mar 2020 417th Jaydosu 387 491 10ms 22 Oct 2021 417th vishwathg 387 491 10ms 19 Aug 2022 417th grieve 387 491 9ms 9 Jun 2023 417th davidtiemstra 387 491 10ms 11 Jul 2023 417th Itnug 387 491 10ms 19 Jul 2023 417th Glinte 387 491 10ms 29 Dec 2023 417th fkantelberg 387 491 11ms 15 Jul 2025 417th cthierfelder 🇲🇨 387 491 10ms 5 Sep 2025 417th Matter1024 🇮🇳 387 491 10ms 7 days ago 427th GreenyNeko 386 492 10ms 24 Jul 2020 427th ydevor 🇮🇱 386 492 10ms 20 Nov 2020 427th michael-alperovich 386 492 9ms 1 Feb 2021 427th richard-oelze 🇩🇪 386 492 10ms 28 Nov 2021 427th MichaelMBradley 🇨🇦 386 492 10ms 5 Apr 2022 427th P-Quentin 🇫🇷 386 492 10ms 3 Aug 2022 427th DragonaireM 386 492 10ms 4 Feb 2023 427th ocean0821 386 492 10ms 7 May 2025 435th bthalheim 385 493 10ms 1 Aug 2022 435th TeddyWoodburn 385 493 29ms 6 Oct 2024 435th rothos 385 493 10ms 31 Dec 2024 435th M4rc0g1 385 493 11ms 16 Nov 2025 439th schachmattmatt 385 494 10ms 11 Aug 2021 439th specbug 385 494 10ms 30 Nov 2022 439th zsimo-lab49 385 494 10ms 15 May 2023 442nd evanrittner 384 495 10ms 26 Feb 2021 442nd Re-Adventures 🇮🇳 384 495 9ms 29 Mar 2021 442nd kaptsanovb 384 495 10ms 4 Apr 2022 442nd kenny14231 384 495 10ms 5 Aug 2022 442nd OrangeBacon 384 495 10ms 31 Jul 2024 442nd Unknownuserfrommars 384 495 9ms 7 Oct 2024 448th YoungjuneKwon 383 496 10ms 20 Nov 2020 448th asheeri 383 496 10ms 15 Aug 2021 448th ZakkkkAttackkkk 🇵🇭 383 496 30ms 25 Dec 2021 448th try-except-try-accept 🇹🇭 383 496 9ms 9 Jul 2022 448th ramsay 383 496 10ms 8 Aug 2022 448th jeaosh 383 496 10ms 22 Oct 2022 448th Starwort 🇬🇧 383 496 11ms 4 Dec 2022 448th fenix-bear 383 496 10ms 3 Jul 2023 448th htareque 383 496 30ms 18 Oct 2023 448th khavik 383 496 10ms 11 May 2024 448th yashima 383 496 9ms 4 Nov 2024 448th bogosorter 383 496 10ms 9 Jul 2025 448th celiendonze 🇨🇭 383 496 10ms 18 Dec 2025 461st btjones0 382 497 10ms 26 Dec 2020 461st vezzick 382 497 10ms 7 Mar 2021 461st kaylacomer 382 497 10ms 24 Oct 2021 461st MCausc78 🇺🇦 382 497 10ms 5 Jan 2023 461st ZoeyKD 382 497 9ms 14 May 2023 461st xoxo-ily 382 497 10ms 12 Dec 2023 461st aloobun 382 497 10ms 2 Dec 2024 468th SimonPeatman 382 498 10ms 29 Dec 2018 468th Arkaedan 382 498 9ms 27 Jul 2020 468th cesarm4 382 498 10ms 30 Aug 2021 468th GeneralTwi 382 498 10ms 4 May 2022 468th n0es 382 498 10ms 6 Oct 2022 468th saoudi-h 382 498 10ms 12 Jan 2023 468th adamnielson42 🇺🇸 382 498 9ms 30 May 2023 468th ArchFin 382 498 9ms 21 Nov 2024 468th GeneralFabian 382 498 31ms 14 Dec 2024 468th energee 382 498 10ms 19 Dec 2024 468th Europe2048 382 498 9ms 17 Sep 2025 468th muratovm 382 498 10ms 10 Dec 2025 480th orifu 381 499 9ms 22 Feb 2021 First Prev 401–480 of 1,169 Next Last