The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 3 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 879th falinos 340 561 10ms 1 Jan 2023 879th andyxukq 340 561 10ms 4 Feb 2025 883rd zgialor-lab 340 562 10ms 18 days ago 884th fl3ur1nestimable 339 563 10ms 28 Mar 2022 885th NuqieNoila 339 564 9ms 1 Feb 2019 885th Saaxxx 339 564 10ms 22 Aug 2023 887th MiranDaniel 🇨🇿 338 565 17ms 30 Aug 2023 887th pquline 338 565 9ms 5 Mar 2025 889th artur-py 337 566 10ms 16 Dec 2022 889th skarabb 337 566 10ms 26 Mar 2024 891st CRHillman 336 568 10ms 14 Aug 2018 891st Greguhh 336 568 10ms 22 Oct 2024 893rd msrawson 336 569 9ms 13 Aug 2018 893rd TJK-S 336 569 10ms 25 Oct 2025 893rd mmarkakis 336 569 10ms 1 Dec 2025 893rd punoko 336 569 10ms 9 Dec 2025 897th ei14 335 570 10ms 18 Jun 2021 897th amollberg 🇸🇪 335 570 10ms 3 Jan 2022 897th Eulentier161 335 570 18ms 30 Aug 2023 900th te-chnical 335 571 10ms 23 Dec 2025 901st Watermelon876 334 572 10ms 27 Nov 2021 901st markbyrne 334 572 10ms 25 Aug 2022 901st joonaspu 334 572 10ms 3 Jun 2023 901st alfonsoalves 334 572 10ms 27 Feb 2024 905th BenAns 333 573 10ms 17 Nov 2018 905th KevinLaux 333 573 11ms 4 Dec 2022 907th Dejgz 332 575 10ms 11 Sep 2023 907th gigaprofisi 🇺🇸 332 575 11ms 2 Mar 2025 909th sayloren 332 576 10ms 30 Jul 2025 910th anananlyjlyj 331 577 10ms 2 Jul 2018 910th Sami-ul 331 577 11ms 12 Oct 2021 910th godCoderXYZ 331 577 10ms 5 Dec 2024 913th omgardner 330 578 10ms 1 Mar 2019 913th samual-hain 330 578 10ms 4 Apr 2024 913th JMMMMC 330 578 12ms 23 Oct 2024 916th bakaq 330 579 10ms 4 Jan 2020 916th danielweper 330 579 11ms 21 Oct 2021 918th NoneTheFewer 329 581 10ms 27 Dec 2025 919th Matistjati 328 582 10ms 17 Feb 2020 920th jpyCode 328 583 10ms 14 Jan 2019 921st osNiko 🇧🇷 326 585 11ms 25 Dec 2025 922nd selketdaly 325 587 10ms 21 Feb 2021 922nd DePopadopalis 325 587 10ms 6 Apr 2022 922nd julienlamoureux78 325 587 11ms 17 Aug 2022 925th benanlam 325 588 10ms 20 Dec 2025 926th dlevear 324 589 10ms 20 May 2021 926th PrinceSalatyell 324 589 9ms 22 Jun 2022 928th maxliuql 324 590 9ms 11 Jul 2025 929th joel-e-m-mitchell 323 591 10ms 10 Jun 2018 929th Nektar24 323 591 10ms 2 Jun 2023 929th Nightmarius 323 591 17ms 22 Jan 2024 932nd bnuh 323 592 10ms 3 Dec 2022 932nd omero-san 323 592 10ms 15 Sep 2025 934th plainoldcheese 🇦🇶 322 594 10ms 16 Apr 2020 935th lewisdean98 321 595 30ms 4 Dec 2022 935th atrus159 321 595 10ms 24 Oct 2023 937th ktnguyen2 320 597 10ms 4 Jan 2020 937th halp1 320 597 10ms 7 Apr 2022 939th jjbvtk 319 598 10ms 31 Aug 2021 939th lethan3 319 598 9ms 1 Dec 2022 941st Modeba 319 599 10ms 5 Nov 2025 942nd clodalala 318 600 10ms 1 Nov 2019 943rd dylanjones92 315 606 10ms 19 Jan 2024 944th zuparnowa 315 607 9ms 28 Jan 2019 944th henrytranter 315 607 10ms 20 Sep 2019 946th Piccora 314 608 10ms 3 Oct 2022 946th Baxi-codes 314 608 10ms 4 Jan 2023 948th FJSFerreira 314 609 10ms 22 May 2021 949th besasam 313 610 9ms 31 Mar 2021 949th OddAlgorithm 313 610 10ms 4 Dec 2022 951st surbainczyk 313 611 10ms 22 Jul 2022 952nd lakshmanaprasanth 311 615 10ms 10 Jun 2021 953rd mhenion8293 🇺🇸 310 616 10ms 11 Jan 2022 953rd kelseychristensen 310 616 11ms 3 Nov 2022 953rd jrappeneker 310 616 10ms 24 Apr 2025 956th warrinerbros 309 618 10ms 3 Dec 2021 957th valgardg 🇮🇸 308 620 16ms 17 Aug 2021 958th delphonso 308 621 10ms 17 Dec 2021 958th Knight333 308 621 9ms 26 Dec 2023 960th MadasMatt4 307 623 10ms 29 Jan 2020 First Prev 881–960 of 1,168 Next Last