The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 6 days. Why not try and solve them ahead of time?
Collatz 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 198th BREMAUCY 🇫🇷 781 73 22ms 24 Aug 2025 198th FortuiteMan 🇫🇷 781 73 20ms 28 Sep 2025 198th miaoaixuan 781 73 21ms 30 Sep 2025 198th Lv0Sys 🇵🇱 781 73 25ms 7 Dec 2025 198th zacharysfrazee 781 73 21ms 11 Jan 2026 198th bpharaldsson 781 73 20ms 6 Feb 2026 247th TobyBoyne 🇬🇧 770 74 19ms 4 May 2022 247th RDShah 770 74 21ms 6 May 2022 247th Indivicivet 770 74 20ms 9 May 2022 247th CedricGebistorf 770 74 20ms 9 May 2022 247th ophact 770 74 22ms 11 May 2022 247th ImpressedByRocks 770 74 20ms 17 May 2022 247th LHuitre 770 74 19ms 2 Jun 2022 247th neihousaigaai 770 74 18ms 8 Jun 2022 247th rowboat1 770 74 20ms 10 Jun 2022 247th inverseLorentz 🇦🇺 770 74 20ms 13 Jun 2022 247th clementblaudeau 770 74 25ms 29 Jun 2022 247th adoxography 770 74 20ms 13 Jul 2022 247th Attero 🇸🇪 770 74 20ms 20 Jul 2022 247th Heathcorp 🇦🇺 770 74 19ms 27 Jul 2022 247th jfallon1997 770 74 20ms 11 Aug 2022 247th VictorFordham 770 74 24ms 26 Aug 2022 247th georgehulme 770 74 19ms 1 Sep 2022 247th smartiel 770 74 21ms 15 Sep 2022 247th trist224 🇫🇷 770 74 20ms 21 Sep 2022 247th Kloppermand 🇩🇰 770 74 19ms 7 Oct 2022 247th knutae 🇳🇴 770 74 19ms 9 Oct 2022 247th Troon 770 74 18ms 14 Oct 2022 247th MaxElf999 770 74 20ms 14 Oct 2022 247th SniperSmiley 🇺🇸 770 74 20ms 6 Dec 2022 247th elephantpanda 770 74 21ms 10 Dec 2022 247th ArthurBond 770 74 19ms 19 Dec 2022 247th Larspolo 770 74 20ms 25 Dec 2022 247th dcc5480 770 74 19ms 12 Jan 2023 247th Ripick 770 74 20ms 1 Feb 2023 247th m3nt0ras 🇬🇷 770 74 19ms 3 Feb 2023 247th Skwerl23 770 74 19ms 5 Feb 2023 247th frankgraziano 770 74 18ms 19 Feb 2023 247th KenanHanke 770 74 20ms 21 Feb 2023 247th DanielPeterssonAI 770 74 20ms 13 Mar 2023 247th jiaminglimjm 🇲🇾 770 74 20ms 20 Mar 2023 247th ejini6969 770 74 18ms 22 Mar 2023 247th GulgDev 770 74 19ms 22 Mar 2023 247th vrnprkh 770 74 19ms 30 Mar 2023 247th RuyiLi 770 74 21ms 1 Apr 2023 247th StardustGogeta 770 74 19ms 7 May 2023 247th zbreit 🇺🇸 770 74 20ms 7 May 2023 247th kyleclaassen 770 74 20ms 20 May 2023 247th mbittner20 770 74 20ms 27 May 2023 247th tweska 🇳🇱 770 74 20ms 5 Jun 2023 247th cros107 🇦🇺 770 74 21ms 11 Aug 2023 247th yourlefthandman 770 74 20ms 16 Aug 2023 247th daisyyedda 770 74 21ms 17 Aug 2023 247th cesarm4 770 74 19ms 29 Aug 2023 247th midnattssol 🇸🇪 770 74 20ms 22 Sep 2023 247th lambda-abstraction 770 74 20ms 21 Oct 2023 247th levavft 770 74 20ms 26 Oct 2023 247th Buecherfresser 770 74 19ms 22 Nov 2023 247th anarconic 770 74 50ms 8 Dec 2023 247th azure-blondon 770 74 19ms 11 Dec 2023 247th kurkale6ka 770 74 22ms 20 Dec 2023 247th Anonymousellama21 770 74 22ms 14 Mar 2024 247th Bmrl7 770 74 20ms 23 Mar 2024 247th cefqrn 770 74 20ms 26 May 2024 247th drochom 770 74 19ms 18 Jun 2024 247th hiichbindermax 770 74 19ms 22 Jun 2024 247th cykim8811 770 74 45ms 11 Jul 2024 247th imelxr 🇮🇱 770 74 25ms 17 Aug 2024 247th EnTerr 770 74 20ms 25 Aug 2024 247th Mabeloid 🇳🇴 770 74 20ms 1 Sep 2024 247th madeforlosers 770 74 19ms 5 Sep 2024 247th LostSyntax21 🇬🇧 770 74 19ms 10 Sep 2024 247th Deedogg 770 74 19ms 11 Sep 2024 247th MassimoParisi 770 74 21ms 18 Sep 2024 247th agreegious 770 74 19ms 17 Nov 2024 247th Stockoh 🇫🇷 770 74 27ms 17 Nov 2024 247th Andrey135296 770 74 22ms 24 Nov 2024 247th TralfamadorianComedian 770 74 18ms 6 Dec 2024 247th bltnppcnt 770 74 36ms 3 Jan 2025 247th ZorblaxV 770 74 21ms 12 Jan 2025 First Prev 241–320 of 841 Next Last
