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?
Inventory Sequence 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 71st elana-teal 864 59 12ms 20 Jun 2025 71st dirckvdende 864 59 11ms 11 Jul 2025 71st Lv0Sys 🇵🇱 864 59 33ms 7 Dec 2025 71st aksyristos 864 59 34ms 16 hours ago 85th OllieBoyne 🇬🇧 850 60 34ms 6 Dec 2022 85th AlexanderFair 850 60 33ms 2 Jul 2023 85th bzijlema 🇳🇱 850 60 33ms 11 Nov 2023 85th ahmetdemirag 🇨🇾 850 60 30ms 21 Jul 2024 85th dokutan 850 60 42ms 21 Aug 2024 85th BlankSpruce 850 60 11ms 26 Apr 2025 85th jipsong 🇩🇪 850 60 41ms 13 Jun 2025 85th webmiche 850 60 12ms 28 Nov 2025 85th CommandLeo 🇮🇹 850 60 33ms 7 Jan 2026 85th 051 🇸🇬 850 60 34ms 8 Jan 2026 95th thehylian 836 61 33ms 11 Jan 2023 95th galloj 🇨🇿 836 61 36ms 4 Mar 2023 95th commandz0 🇺🇸 836 61 30ms 17 Nov 2023 95th mathisfun271 836 61 33ms 13 Feb 2024 95th BREMAUCY 🇫🇷 836 61 33ms 7 Mar 2024 95th stertooy 🇧🇪 836 61 31ms 10 Jun 2024 95th tri1212 🇻🇳 836 61 42ms 30 Jun 2024 95th Alex-x90 🇺🇸 836 61 11ms 20 Nov 2024 95th solisolu 836 61 30ms 2 Dec 2025 95th Googolplexo 🇷🇺 836 61 34ms 45 hours ago 105th rak1507 🇬🇧 823 62 31ms 22 Nov 2022 105th fourth-bit 823 62 35ms 7 Dec 2022 105th SniperSmiley 🇺🇸 823 62 33ms 10 Dec 2022 105th Fracture17 823 62 32ms 14 Apr 2023 105th quimey 823 62 35ms 23 Jun 2023 105th dranjohn 823 62 50ms 11 Sep 2023 105th RedzGoose 🇦🇺 823 62 12ms 17 Jun 2024 105th smilesformiles3 823 62 11ms 21 Jun 2025 105th 77Tigers 823 62 32ms 13 Jan 2026 114th guilhem-roy 🇫🇷 810 63 37ms 21 Nov 2022 114th nstearns96 🇬🇧 810 63 31ms 6 Jan 2023 114th Tess2662 810 63 11ms 4 Mar 2023 114th lhulinsky 810 63 36ms 23 Oct 2024 114th croc54 810 63 48ms 8 Jan 2025 114th andrewjc2000 810 63 38ms 29 Jul 2025 114th KasperKivimaeki 🇫🇮 810 63 29ms 25 Oct 2025 121st CedricGebistorf 797 64 34ms 4 May 2023 121st cros107 🇦🇺 797 64 36ms 5 Oct 2023 121st logvp 797 64 32ms 3 Jan 2024 121st namelessiw 797 64 34ms 10 Jan 2024 121st jmfk 797 64 39ms 5 Apr 2024 121st hiichbindermax 797 64 40ms 4 Sep 2024 121st madex 🇩🇪 797 64 14ms 12 days ago 128th mrnomm 785 65 15ms 6 Apr 2023 128th suwat513 785 65 37ms 19 Jun 2023 128th neihousaigaai 785 65 16ms 13 Feb 2024 128th Stockoh 🇫🇷 785 65 40ms 26 Apr 2024 128th willschremmer 785 65 21ms 11 May 2024 128th CLOStrophobic 🇮🇹 785 65 11ms 31 Jan 2025 128th JunkIce 785 65 15ms 13 Feb 2025 128th TheZwierzLF 🇵🇱 785 65 34ms 27 May 2025 128th rucin93 🇵🇱 785 65 22ms 31 May 2025 128th Bmrl7 785 65 15ms 23 Dec 2025 138th mdnestor 773 66 41ms 23 Dec 2022 138th jared-hughes 773 66 11ms 16 Mar 2023 138th fgrosshans 🇫🇷 773 66 44ms 14 Jul 2024 138th codingisgreatbutiamnot 773 66 40ms 9 Aug 2024 138th hellwue 773 66 44ms 4 Sep 2024 138th iczelia 🇩🇪 773 66 32ms 23 Oct 2025 138th Europe2048 773 66 15ms 13 days ago 145th vishwathg 761 67 29ms 4 Feb 2023 145th Yewzir 🇧🇪 761 67 16ms 7 Feb 2024 145th wh3n3v3r 🇨🇿 761 67 18ms 14 Nov 2024 145th jamesthekee 761 67 14ms 25 Jan 2025 149th MichalMarsalek 🇨🇿 750 68 23ms 20 Nov 2022 149th jmerle 🇳🇱 750 68 22ms 11 Jul 2023 149th nemoyatpeace 750 68 15ms 15 Jan 2026 152nd andre-lameirinhas 🇵🇹 739 69 15ms 23 Feb 2023 152nd jtaxen 739 69 15ms 30 Mar 2024 152nd FranklinJiaChen 739 69 39ms 5 Aug 2024 155th b10011 🇫🇮 729 70 16ms 9 Jan 2023 155th Just4FunCoder 729 70 41ms 23 Mar 2023 155th knutae 🇳🇴 729 70 15ms 29 Dec 2023 155th wobblybits 729 70 17ms 18 Aug 2025 155th jacekwladzinski 729 70 29ms 4 Oct 2025 160th PyryL 🇫🇮 718 71 16ms 23 Aug 2024 First Prev 81–160 of 246 Next Last