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 480th Bombergames 381 499 10ms 21 Jan 2022 480th deerfarce 381 499 10ms 23 Dec 2022 480th bob-th 381 499 10ms 29 Dec 2022 480th DonCharlesLambert 381 499 11ms 15 Feb 2024 480th hiichbindermax 381 499 9ms 3 Sep 2024 480th jasonxue1 381 499 10ms 26 Jul 2025 480th yukii1004 381 499 10ms 25 Sep 2025 480th yujqiao 381 499 9ms 16 Dec 2025 489th Psirving 380 500 10ms 20 Jul 2020 489th stephenuniverse 380 500 10ms 23 Aug 2021 489th Giridesh 380 500 10ms 3 Apr 2022 489th kimbo 🇺🇸 380 500 9ms 4 Dec 2022 489th Bmrl7 380 500 9ms 19 Mar 2024 489th planeklm 380 500 10ms 17 Dec 2024 489th raymur 380 500 10ms 26 Jun 2025 489th oween12 380 500 11ms 6 Aug 2025 489th estrawitch 380 500 10ms 15 days ago 498th adoxography 379 501 9ms 30 Mar 2018 498th sambirnbaum1 379 501 11ms 7 Sep 2019 498th ArturLukianov 379 501 10ms 27 Dec 2020 498th suhasdara 379 501 11ms 11 Sep 2022 498th ceeb9 379 501 10ms 5 May 2023 498th DrPrettyman 379 501 10ms 31 May 2023 498th lucaswiman 379 501 10ms 13 Aug 2023 498th damoose717 379 501 10ms 23 May 2025 498th bknower 379 501 10ms 25 Jun 2025 507th djtuBIG-MaliceX 378 502 16ms 30 Jan 2018 507th The3gs 378 502 10ms 13 Oct 2020 507th 77Tigers 378 502 10ms 28 Feb 2021 507th b4dpxl 378 502 9ms 10 Nov 2021 507th BrenSchaap 378 502 10ms 11 Nov 2021 507th firegene 🇮🇪 378 502 10ms 16 Dec 2021 507th thiccaxe 378 502 10ms 2 Oct 2022 507th EyalLitvin 378 502 10ms 16 Nov 2022 507th mikehanus 378 502 9ms 21 Nov 2023 516th kypi 378 503 10ms 20 Feb 2020 516th bastienvoirin 🇫🇷 378 503 11ms 28 Nov 2020 516th bbakersmith 378 503 10ms 26 Jul 2021 516th HassanAliKadhem 🇧🇭 378 503 30ms 5 Jan 2022 516th Expurple 378 503 10ms 8 Jan 2022 516th johnellis1392 378 503 10ms 5 Jan 2024 516th ImpressedByRocks 378 503 9ms 13 Mar 2024 516th Benzamp 378 503 10ms 26 Feb 2026 524th ArturLange 377 504 10ms 31 Aug 2018 524th NoliHyd 377 504 9ms 11 Oct 2018 524th badboj40 377 504 9ms 18 Jan 2023 524th unknown25001 377 504 10ms 18 Jul 2024 524th PyryL 🇫🇮 377 504 9ms 12 Aug 2024 524th Marsolo1 377 504 10ms 24 Sep 2024 530th Smoncko 376 505 13ms 1 Feb 2023 530th jrbud 376 505 10ms 30 Dec 2023 530th xiaoyiming123 376 505 10ms 11 Aug 2025 530th OSYCh314 🇦🇺 376 505 10ms 12 Feb 2026 530th wdarling-cohere 376 505 10ms 24 days ago 535th mizuzimu 375 506 9ms 4 Feb 2020 535th mokymok 🇺🇸 375 506 10ms 1 Dec 2021 535th AlexanderFair 375 506 10ms 18 Jul 2023 535th yuchuehw 375 506 9ms 4 Jan 2024 535th cykim8811 375 506 10ms 11 Jul 2024 535th 40fied4t 375 506 10ms 15 May 2025 535th Rogacz 375 506 10ms 9 Jun 2025 535th MyckollWinchester 375 506 9ms 10 Dec 2025 543rd JBcoding 375 507 16ms 7 Sep 2020 543rd Thinthiner 375 507 17ms 7 Sep 2020 543rd bsoyka 🇺🇸 375 507 11ms 30 Dec 2022 543rd ozzypossie 375 507 11ms 26 May 2023 543rd qwertzuioppel 375 507 10ms 4 Mar 2024 543rd gyanesh-maurya 375 507 9ms 28 Dec 2025 549th TrAyZeN 374 508 10ms 18 Aug 2019 549th befoster 374 508 9ms 10 Apr 2021 549th pranavcode 374 508 31ms 26 Apr 2021 549th Cloakless 🇬🇧 374 508 16ms 18 Oct 2021 549th frankgraziano 374 508 10ms 14 Feb 2023 549th tejapvk 374 508 10ms 18 Jun 2025 549th wboka 374 508 10ms 25 Dec 2025 556th byteJager 373 509 11ms 3 Jan 2021 556th walterfeyman 373 509 10ms 30 Oct 2021 556th rollershutter 373 509 11ms 30 Nov 2021 556th gamer0kayf1n3 373 509 9ms 3 Jun 2022 556th RoscoeSmith 373 509 10ms 8 Sep 2022 First Prev 481–560 of 1,169 Next Last