The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 8 days. Why not try and solve them ahead of time?
Leap Years 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 223rd mokymok 🇺🇸 827 52 16ms 14 Jun 2021 223rd jacklynnepenick 827 52 21ms 27 Aug 2021 223rd Y0UR-U5ERNAME 827 52 16ms 5 Sep 2021 223rd itsjustfreekie 827 52 39ms 22 Sep 2021 223rd Natanaelel 🇸🇪 827 52 16ms 10 Oct 2021 223rd sleepyStick 827 52 15ms 2 Dec 2021 223rd Stockoh 🇫🇷 827 52 21ms 18 Dec 2021 223rd petroselo 827 52 16ms 29 Dec 2021 223rd fynnkroeger 827 52 13ms 29 Jan 2022 223rd Bonjour27891 🇻🇳 827 52 41ms 9 Feb 2022 223rd j-Ewan 827 52 12ms 2 Mar 2022 223rd CedricGebistorf 827 52 10ms 2 Mar 2022 223rd tkr-sh 🇰🇵 827 52 42ms 24 Apr 2022 223rd vhoulbreque 🇫🇷 827 52 16ms 11 Aug 2022 223rd kenny14231 827 52 17ms 17 Aug 2022 223rd MaxElf999 827 52 10ms 22 Sep 2022 223rd Drew-j-Smith 827 52 10ms 5 Nov 2022 223rd CatsAreFluffy 827 52 18ms 6 Nov 2022 223rd goGuru 827 52 11ms 23 Dec 2022 223rd jfallon1997 827 52 10ms 4 Jan 2023 223rd mathb0y512 827 52 17ms 5 Jan 2023 223rd fredrik-bakke 🇳🇴 827 52 10ms 26 Jan 2023 223rd aksyristos 827 52 9ms 30 Jan 2023 223rd vishwathg 827 52 20ms 7 Apr 2023 223rd Fracture17 827 52 13ms 9 Apr 2023 223rd adamnielson42 🇺🇸 827 52 13ms 25 Apr 2023 223rd falsidge 827 52 10ms 10 Jul 2023 223rd anonymaew 827 52 13ms 2 Aug 2023 223rd fkantelberg 827 52 42ms 8 Aug 2023 223rd namelessiw 827 52 10ms 10 Jan 2024 223rd SB-945 827 52 9ms 21 Feb 2024 223rd Anonymousellama21 827 52 14ms 14 Mar 2024 223rd elgan65536 🇺🇸 827 52 12ms 30 Mar 2024 223rd northsuperman 827 52 16ms 31 Mar 2024 223rd ahmetdemirag 🇨🇾 827 52 14ms 6 Jun 2024 223rd stertooy 🇧🇪 827 52 9ms 10 Jun 2024 223rd hacker112 🇸🇪 827 52 17ms 22 Jun 2024 223rd CutSandstone 827 52 20ms 8 Jul 2024 223rd NerdyMcNerd42 827 52 10ms 20 Jul 2024 223rd sjrct 827 52 12ms 4 Aug 2024 223rd ashchen738 827 52 16ms 6 Oct 2024 223rd jeremylliu 827 52 17ms 6 Oct 2024 223rd elana-teal 827 52 10ms 21 Jun 2025 223rd csharpython 827 52 16ms 23 Jul 2025 223rd andrewjc2000 827 52 20ms 18 Aug 2025 223rd Troon 827 52 9ms 26 Aug 2025 223rd Andrey2001 827 52 16ms 26 Nov 2025 223rd GodlyProgrammer1 827 52 21ms 1 Dec 2025 223rd kellantech 827 52 10ms 17 Dec 2025 223rd denkyuu1 827 52 16ms 30 Jan 2026 291st ay2718 811 53 16ms 19 Aug 2019 291st mortimervonchappuis 811 53 10ms 16 Mar 2020 291st giacomogallina 811 53 10ms 10 Jun 2020 291st PatrickStephansen 🇿🇦 811 53 16ms 7 Sep 2020 291st vprab 811 53 17ms 8 Dec 2020 291st sandybeachum 811 53 9ms 16 Mar 2021 291st Larspolo 811 53 10ms 4 Jun 2021 291st maddenfederico 811 53 13ms 30 Aug 2021 291st Fishron 811 53 21ms 18 Oct 2021 291st cubed-guy 811 53 16ms 18 Oct 2021 291st vodker1 811 53 10ms 9 Mar 2022 291st glesnick 811 53 17ms 18 Aug 2022 291st QuincyNash 🇺🇸 811 53 9ms 5 Dec 2022 291st Wanderkind 🇰🇷 811 53 10ms 9 Jan 2023 291st NDR0216 🇹🇼 811 53 10ms 13 Feb 2023 291st markusgraube 811 53 10ms 11 Apr 2023 291st Igyeom 🇰🇷 811 53 10ms 11 Jun 2023 291st mhgockel 811 53 11ms 23 Jul 2023 291st hiichbindermax 811 53 9ms 4 Aug 2023 291st jacobly0 🇺🇸 811 53 11ms 21 Sep 2023 291st Betuaredead 811 53 16ms 12 Nov 2023 291st Schreipfelerer 811 53 12ms 27 Nov 2023 291st roguh 🇬🇹 811 53 9ms 29 Dec 2023 291st hyw498169842 811 53 10ms 13 Jan 2024 291st wuzekai518 811 53 16ms 16 Jul 2024 291st o0BlackDragon0o 811 53 15ms 6 Sep 2024 291st Bombalech 811 53 16ms 7 Sep 2024 291st mrondon8 811 53 18ms 2 Dec 2024 291st zgialor-lab 811 53 10ms 2 Feb 2026 291st FranklinJiaChen 811 53 16ms 16 Feb 2026 First Prev 241–320 of 1,122 Next Last