The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 30 hours. 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 800th Guptacos 349 544 10ms 2 Aug 2020 800th Pargolo 349 544 10ms 7 Oct 2021 800th humz2k 349 544 10ms 5 Jul 2022 800th AharonSambol 349 544 16ms 18 Aug 2023 800th AthiraPillai123 349 544 9ms 4 Jan 2024 800th multikatt 349 544 9ms 13 Jan 2026 800th davidludwik2370 349 544 10ms 22 days ago 808th dzshn 349 545 10ms 25 Nov 2020 808th jellybro99 349 545 9ms 15 Oct 2021 808th StoverGitHub 349 545 11ms 16 Jun 2022 808th Bananapants22 349 545 9ms 15 Aug 2022 808th bedwards 349 545 10ms 13 Jan 2025 813th llysnafedd 348 546 10ms 28 Aug 2020 813th alexstarosta 348 546 10ms 27 Jun 2024 813th kyleyarwood 348 546 9ms 4 Oct 2024 813th jwfiredragon 348 546 11ms 15 May 2025 817th smf0x10 347 547 10ms 3 Oct 2021 817th Eilonlif 🇮🇱 347 547 10ms 25 Dec 2022 817th b20fuji 347 547 10ms 18 Oct 2023 817th Amy-Checcllo 347 547 9ms 22 Sep 2024 817th GeorgeStatho 347 547 11ms 5 Aug 2025 822nd DylanScottCarroll 347 548 10ms 8 Nov 2021 822nd RubiksImplosion 347 548 10ms 4 Dec 2022 822nd felixcroc 347 548 11ms 1 Apr 2023 822nd epic-programmer-guy 347 548 10ms 29 Dec 2023 822nd MassimoParisi 347 548 16ms 24 Sep 2024 822nd Shotokhan 347 548 10ms 15 Sep 2025 822nd Evytag 🇫🇷 347 548 10ms 9 Oct 2025 829th afyber 346 549 9ms 26 Jun 2019 829th my1e5 346 549 9ms 29 Nov 2021 829th oakesy 346 549 10ms 19 May 2024 829th CyberTapir 346 549 10ms 30 Aug 2024 829th martindotexe 🇳🇴 346 549 17ms 15 Feb 2025 829th shawncrabtree 346 549 10ms 21 Jun 2025 829th Sharrrkkk 346 549 10ms 21 Jul 2025 836th Esterfox610 345 550 10ms 17 Aug 2022 836th llama1024 345 550 10ms 5 Dec 2022 836th lorienaquarius 345 550 10ms 31 Dec 2023 839th eoinfennessy 345 551 10ms 21 Jul 2021 839th micah-weitzman 345 551 10ms 27 Jul 2021 839th mehekj 345 551 10ms 29 Jul 2021 839th No-Jons 345 551 9ms 23 May 2022 843rd Parapet128 344 552 9ms 17 Jan 2019 843rd dillon-duncando 344 552 10ms 19 Dec 2021 843rd nmougino 🇫🇷 344 552 17ms 31 May 2022 843rd Vaibhav0460 344 552 10ms 16 Feb 2024 843rd navier-1 344 552 10ms 15 Sep 2025 843rd kasarino 344 552 10ms 30 Nov 2025 849th aazuspan 344 553 10ms 24 Nov 2021 849th leeyonjae 344 553 11ms 10 Dec 2023 849th jjkochan2 344 553 9ms 17 Jan 2025 852nd carsonsyberg 343 554 11ms 9 May 2022 853rd Alexander-Francis 342 555 10ms 10 Jul 2019 853rd itiievskyi 🇺🇦 342 555 10ms 10 Aug 2020 853rd KasperKivimaeki 🇫🇮 342 555 10ms 20 Nov 2025 853rd pingpwn 342 555 10ms 14 Feb 2026 857th dddthedark 342 556 10ms 21 Jun 2019 857th ejerrard 342 556 10ms 27 Aug 2020 857th robertovers 342 556 14ms 29 Sep 2023 857th imnotAlexKnight 342 556 10ms 10 Jul 2025 857th rahulbyte-js 342 556 10ms 25 Nov 2025 862nd amadeusdotpng 341 558 10ms 22 Apr 2023 862nd iliao2345 341 558 10ms 8 Jul 2025 864th lmolteno 340 559 10ms 3 Mar 2021 864th jmath3912 340 559 10ms 26 Apr 2024 866th estomagordo 🇳🇱 339 560 10ms 3 Aug 2019 866th gautambp 339 560 18ms 22 Jun 2025 866th iilegacyyii 339 560 17ms 30 Dec 2025 869th kalpanasuresh 339 561 10ms 26 Mar 2021 869th luxdragon 339 561 10ms 11 Oct 2022 869th falinos 339 561 10ms 1 Jan 2023 869th andyxukq 339 561 10ms 4 Feb 2025 873rd zgialor-lab 338 562 10ms 20 days ago 874th fl3ur1nestimable 337 563 10ms 28 Mar 2022 875th NuqieNoila 337 564 9ms 1 Feb 2019 875th bwenstar 337 564 10ms 9 Aug 2022 875th Saaxxx 337 564 10ms 22 Aug 2023 878th MiranDaniel 🇨🇿 336 565 17ms 30 Aug 2023 878th pquline 336 565 9ms 5 Mar 2025 880th artur-py 336 566 10ms 16 Dec 2022 First Prev 801–880 of 1,171 Next Last