The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 34 hours. Why not try and solve them ahead of time?
Reversi 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 1st 4atj 1,000 82 25ms 8 Apr 2025 2nd m-tkach 🇺🇦 953 86 18ms 2 Jun 2024 2nd Steffan153 🇫🇮 953 86 19ms 21 Feb 2026 4th xsot 🇸🇬 943 87 17ms 2 Jun 2024 4th JayXon 🇺🇸 943 87 19ms 2 Jun 2024 4th pardouin 🇫🇷 943 87 19ms 12 Jul 2024 4th GrayJoKing 🇦🇺 943 87 19ms 23 Jul 2024 4th sean-niemann 🇺🇸 943 87 18ms 4 Feb 2025 4th Seek64 🇩🇪 943 87 20ms 23 May 2025 4th emgordon154 943 87 19ms 6 Jun 2025 4th kg583 🇺🇸 943 87 18ms 25 Aug 2025 12th duckyluuk 🇳🇱 882 93 37ms 15 Aug 2024 13th SirBogman 🇺🇸 863 95 17ms 1 Jun 2024 13th plcc0 863 95 29ms 26 hours ago 15th hallvabo 🇳🇴 854 96 33ms 6 Jun 2024 16th error256 837 98 22ms 1 Jun 2024 17th SB-945 820 100 32ms 8 Jun 2024 18th lifthrasiir 🇰🇷 804 102 71ms 16 Nov 2024 19th snoozingnewt 🇨🇦 774 106 26ms 14 Dec 2025 20th qpwoeirut 766 107 26ms 1 Oct 2025 21st CornerMercury 🇬🇧 739 111 1,507ms 24 Nov 2025 22nd Shanethegamer 🇺🇸 719 114 23ms 8 Apr 2025 23rd albanian-laundromat 701 117 59ms 17 Nov 2025 24th orthoplex 🇨🇽 678 121 22ms 1 Jun 2024 25th nwellnhof 🇩🇪 672 122 18ms 1 Jun 2024 25th MeWhenI 🇻🇦 672 122 26ms 7 Jun 2024 25th sisyphus-ppcg 🇦🇺 672 122 19ms 25 Jul 2024 28th ovs-code 🇩🇪 667 123 18ms 1 Jun 2024 28th ryyyn 🇺🇸 667 123 19ms 5 Nov 2025 30th edsrzf 🇳🇿 656 125 18ms 9 Dec 2025 31st 5cw 🇺🇸 651 126 18ms 1 Jun 2024 31st stefangimmillaro 651 126 18ms 30 Jan 2025 31st bricknellj 651 126 18ms 6 Feb 2025 31st KatieLG 🇬🇧 651 126 2,449ms 15 Sep 2025 31st Flekay 🇩🇪 651 126 16ms 15 Feb 2026 36th AlephSquirrel 641 128 30ms 4 Jun 2024 37th ndren 636 129 304ms 11 Jul 2025 38th jatloe 617 133 362ms 28 Oct 2024 39th GolfingSuccess 🇬🇷 612 134 20ms 1 Jun 2024 40th bzijlema 🇳🇱 603 136 36ms 14 Jan 2026 41st blaztoma 🇱🇹 594 138 25ms 11 Dec 2025 41st Lv0Sys 🇵🇱 594 138 25ms 23 Feb 2026 43rd bizy-coder 590 139 32ms 1 Jun 2024 43rd cros107 🇦🇺 590 139 31ms 19 Jun 2024 45th davecame 586 140 20ms 16 Jul 2024 45th Emutis 🇱🇹 586 140 25ms 12 Dec 2025 47th OllieBoyne 🇬🇧 543 151 29ms 6 Jun 2024 48th commandz0 🇺🇸 539 152 26ms 3 Jun 2024 49th wh3n3v3r 🇨🇿 536 153 52ms 12 Nov 2024 50th ZakkkkAttackkkk 🇵🇭 519 158 43ms 9 Feb 2026 50th dokutan 519 158 19ms 16 days ago 52nd StefanHabel 🇨🇦 503 163 330ms 4 days ago 53rd EnTerr 488 168 19ms 5 Jun 2024 54th anter69 🇭🇺 480 171 28ms 20 Feb 2026 55th ahmetdemirag 🇨🇾 477 172 46ms 5 Feb 2025 56th yuchuehw 456 180 20ms 4 Jun 2024 57th BREMAUCY 🇫🇷 441 186 25ms 4 Oct 2025 57th aksyristos 441 186 20ms 3 days ago 59th Yewzir 🇧🇪 436 188 14ms 10 Jun 2024 60th annaproxy 427 192 199ms 28 Aug 2025 61st Babafaba 414 198 21ms 30 Oct 2025 62nd InigoK 🇺🇸 400 205 25ms 22 Sep 2025 63rd guilhem-roy 🇫🇷 387 212 2,261ms 22 Nov 2025 64th elgan65536 🇺🇸 381 215 14ms 3 Oct 2024 65th YAJUE114514 373 220 14ms 28 Dec 2025 66th TobyBoyne 🇬🇧 368 223 17ms 6 Jun 2024 67th mousetail 🇳🇱 357 230 23ms 22 Sep 2025 68th CaedenHarper 🇨🇦 353 232 24ms 11 Dec 2025 69th HumanoidCPU 350 234 21ms 31 Dec 2025 70th madex 🇩🇪 324 253 21ms 23 Dec 2025 71st msbranicky 323 254 35ms 9 Aug 2024 72nd Bulmenisaurus 317 259 35ms 5 Jan 2025 73rd mathisfun271 309 265 31ms 7 Oct 2024 74th alemelis 268 306 21ms 17 Oct 2024 75th klixel 🇨🇦 261 314 280ms 14 Jul 2025 76th mbittner20 251 327 18ms 28 Apr 2025 77th markusgraube 249 329 17ms 1 Jul 2024 78th FortuiteMan 🇫🇷 246 334 23ms 27 Nov 2025 79th knutae 🇳🇴 239 343 21ms 23 Jun 2024 79th jameswmccarty 239 343 29ms 11 Oct 2024 1–80 of 92 Next Last