The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 4 days. Why not try and solve them ahead of time?
τ 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 80th stefangimmillaro 844 77 11ms 19 Dec 2022 80th snydej 844 77 12ms 3 Dec 2024 80th moustave 844 77 11ms 14 Mar 2025 80th jatloe 844 77 11ms 17 Mar 2025 85th RaBa21 🇭🇺 833 78 13ms 19 Jul 2025 86th nstearns96 🇬🇧 823 79 50ms 23 Oct 2024 87th geofft 813 80 11ms 13 Dec 2020 87th betaveros 813 80 12ms 1 Jan 2023 87th albanian-laundromat 813 80 15ms 12 Jul 2025 90th janbehrens 🇩🇪 802 81 11ms 17 Jun 2023 91st NewDefectus 🇮🇱 793 82 30ms 12 Oct 2020 91st wen1now 793 82 11ms 7 Nov 2023 91st ei14 793 82 31ms 23 May 2024 91st Matter1024 🇮🇳 793 82 11ms 6 days ago 95th thisishowmymindworks 🇳🇴 783 83 11ms 14 Oct 2020 96th yokasuretsu 774 84 12ms 14 Apr 2018 97th HETHAT 🇩🇿 765 85 19ms 3 Aug 2025 97th tomh1012 765 85 11ms 21 days ago 99th Babafaba 756 86 91ms 23 Nov 2025 100th glesnick 730 89 34ms 18 Aug 2022 101st daedals 722 90 15ms 6 Jun 2019 101st Attero 🇸🇪 722 90 20ms 5 Oct 2020 101st knutae 🇳🇴 722 90 15ms 14 Jul 2021 101st DrPiranoid 722 90 14ms 26 Mar 2023 101st fourth-bit 722 90 16ms 23 Jun 2023 101st BREMAUCY 🇫🇷 722 90 14ms 29 Apr 2024 101st qpwoeirut 722 90 26ms 2 Oct 2025 108th jacklynnepenick 707 92 21ms 25 Aug 2021 108th Bonjour27891 🇻🇳 707 92 23ms 2 May 2022 108th CatsAreFluffy 707 92 28ms 7 Dec 2022 108th Lv0Sys 🇵🇱 707 92 15ms 20 Feb 2026 112th ImpressedByRocks 691 94 916ms 22 May 2025 113th btjones0 684 95 18ms 6 Dec 2021 113th quimey 684 95 81ms 17 Mar 2023 115th cros107 🇦🇺 613 106 1,614ms 5 Sep 2025 116th elgan65536 🇺🇸 596 109 2,128ms 6 Apr 2024 116th NickTheEASDude 🇺🇸 596 109 836ms 20 Aug 2024 118th jiaminglimjm 🇲🇾 591 110 15ms 27 Nov 2019 118th commandz0 🇺🇸 591 110 32ms 17 Sep 2022 120th neihousaigaai 586 111 2,572ms 7 May 2021 121st inverseLorentz 🇦🇺 575 113 2,264ms 22 Feb 2024 122nd fgrosshans 🇫🇷 565 115 13ms 8 May 2023 123rd xy3 🇮🇪 551 118 19ms 18 Nov 2021 124th yzhs 🇩🇪 546 119 28ms 28 Jan 2020 124th falsidge 546 119 118ms 17 Jun 2023 126th galloj 🇨🇿 542 120 10ms 25 Jan 2021 126th befoster 542 120 23ms 10 Apr 2021 126th guilhem-roy 🇫🇷 542 120 15ms 9 Mar 2022 126th za3k 542 120 2,339ms 28 Oct 2022 130th adamnielson42 🇺🇸 528 123 48ms 31 Mar 2023 131st Mr-McChicken 524 124 20ms 16 Oct 2023 132nd RYNO8 520 125 2,019ms 27 Aug 2021 133rd fynnkroeger 516 126 432ms 22 Jan 2021 133rd ydevor 🇮🇱 516 126 2,732ms 14 Mar 2021 133rd CutSandstone 516 126 483ms 7 Jul 2024 133rd RandGuy 516 126 17ms 27 Nov 2025 137th Secozzi 512 127 9ms 20 Oct 2020 137th InigoK 🇺🇸 512 127 2,748ms 13 Jun 2023 137th CommandLeo 🇮🇹 512 127 641ms 9 Oct 2025 140th Andrey135296 508 128 45ms 30 Apr 2022 141st Indivicivet 496 131 209ms 24 Oct 2021 142nd amollberg 🇸🇪 489 133 851ms 28 Jan 2022 142nd hellwue 489 133 25ms 17 Feb 2023 144th hiichbindermax 485 134 17ms 14 Feb 2025 145th relet 481 135 15ms 9 Aug 2018 145th jmhowl 481 135 63ms 3 Jun 2020 145th cooljoseph1 481 135 17ms 24 Dec 2023 145th BenjaminHGong 481 135 71ms 23 May 2025 149th chneau 478 136 146ms 25 Apr 2020 149th ehulinsky 🇺🇸 478 136 16ms 10 Nov 2021 149th eiburns 478 136 39ms 26 Sep 2023 152nd dzhang314 471 138 18ms 14 Aug 2019 152nd Yewzir 🇧🇪 471 138 16ms 27 May 2023 152nd roupiq 🇵🇱 471 138 38ms 18 Apr 2024 152nd jfallon1997 471 138 16ms 14 May 2024 156th jameslindesay 468 139 299ms 25 Feb 2021 156th stordev 468 139 39ms 26 Feb 2021 158th cbondurant 464 140 16ms 7 May 2021 158th thehylian 464 140 25ms 17 Sep 2023 160th klixel 🇨🇦 461 141 30ms 17 Oct 2024 First Prev 81–160 of 334 Next Last