The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 5 days. Why not try and solve them ahead of time?
Reversi in all languages 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 401st dokutan 409 334 500ms 5 Jun 2024 402nd aksyristos 407 269 15ms 8 days ago 403rd Yewzir 🇧🇪 405 410 1,223ms 9 Jun 2024 404th dokutan 401 264 483ms 13 days ago 405th Yewzir 🇧🇪 400 302 96ms 19 Dec 2024 406th CaedenHarper 🇨🇦 394 343 456ms 7 Oct 2025 407th LHLaurini 🇧🇷 393 314 2ms 29 Jun 2024 408th dokutan 385 292 153ms 15 Jun 2025 409th dokutan 380 273 3,093ms 23 Oct 2024 410th dokutan 379 237 328ms 14 Jun 2024 411th anter69 🇭🇺 376 291 28ms 19 Feb 2026 412th blaztoma 🇱🇹 371 377 128ms 28 Nov 2025 413th gigaprofisi 🇺🇸 370 308 13ms 1 Nov 2025 414th CaedenHarper 🇨🇦 366 237 2,322ms 30 Sep 2025 415th stefangabos 🇷🇴 364 313 12ms 17 Nov 2025 416th msbranicky 360 288 3,356ms 9 Jan 2025 417th zakariamouhid 360 316 12ms 8 Jun 2024 418th IISResetMe 359 232 1,456ms 14 Jun 2024 419th alemelis 358 306 21ms 17 Oct 2024 420th madex 🇩🇪 356 320 13ms 6 Jun 2024 421st tomh1012 355 384 564ms 12 Nov 2025 422nd yuchuehw 353 310 19ms 4 Jun 2024 423rd klixel 🇨🇦 349 314 280ms 14 Jul 2025 424th dokutan 346 279 21ms 27 Dec 2025 425th MichalMarsalek 🇨🇿 346 352 432ms 7 Jun 2024 426th KatieLG 🇬🇧 343 398 444ms 14 Oct 2024 427th BREMAUCY 🇫🇷 340 322 24ms 24 Aug 2025 428th dokutan 339 256 1,377ms 30 Aug 2025 429th Yewzir 🇧🇪 336 326 15ms 10 Jun 2024 430th mbittner20 335 327 18ms 28 Apr 2025 431st markusgraube 333 329 17ms 1 Jul 2024 432nd Yax42 🇫🇷 328 245 132ms 7 Oct 2025 433rd FortuiteMan 🇫🇷 328 334 23ms 27 Nov 2025 434th knutae 🇳🇴 319 343 21ms 23 Jun 2024 434th jameswmccarty 319 343 29ms 11 Oct 2024 436th Babafaba 317 345 21ms 5 Nov 2025 437th Babafaba 314 337 799ms 30 Oct 2025 438th msbranicky 306 294 213ms 18 Sep 2024 439th adamnielson42 🇺🇸 288 380 16ms 16 Oct 2024 440th Yax42 🇫🇷 278 421 155ms 7 Oct 2025 441st FlorianCassayre 🇫🇷 276 396 55ms 1 Jun 2024 442nd croc54 272 403 14ms 3 Feb 2025 443rd HumanoidCPU 262 417 22ms 31 Dec 2025 444th HumanoidCPU 261 405 744ms 31 Dec 2025 445th jtaxen 258 425 56ms 3 Jun 2024 446th tomh1012 256 427 20ms 18 days ago 447th mrmena 🇦🇺 231 636 44ms 9 Jun 2024 448th iczelia 🇩🇪 219 499 12ms 23 Oct 2025 449th muser-logiccpu 🇺🇦 215 508 17ms 21 Aug 2025 450th scpchicken 🇵🇼 207 529 12ms 1 Jun 2024 451st hiichbindermax 201 545 15ms 4 Jun 2024 451st KatieLG-Transpiler 🇬🇧 201 545 14ms 16 Aug 2024 453rd two-bad 🇬🇧 178 638 16ms 10 Aug 2025 454th Jacob385 150 903 538ms 22 Jun 2024 455th Zhenyu-Bo 131 833 12ms 1 Aug 2025 456th Msleizak 🇫🇷 115 725 344ms 23 Jul 2025 457th KatieLG 🇬🇧 99 3,659 90ms 9 Jun 2024 458th AidanWalter 59 1,869 14ms 28 Nov 2025 459th error256 0 121 1,776ms 4 May 2025 460th ovs-code 🇩🇪 0 126 14ms 20 Jun 2025 461st edsrzf 🇳🇿 0 170 240ms 29 May 2025 462nd aiwana 0 238 40ms 22 Oct 2025 463rd Yewzir 🇧🇪 0 276 3ms 12 Feb 2026 464th dokutan 0 280 68ms 11 days ago 465th dokutan 0 467 62ms 28 Jun 2025 First Prev 401–465 of 465
