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?
Rijndael S-box in all languages 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 641st KatieLG 🇬🇧 279 805 114ms 20 Apr 2025 641st CaedenHarper 🇨🇦 279 805 117ms 1 Dec 2025 643rd gastropner 278 227 1ms 17 Jul 2025 644th dokutan 276 572 2,630ms 24 Oct 2024 645th hellwue 275 311 17ms 10 Sep 2024 645th HumanoidCPU 275 311 11ms 12 Nov 2025 647th theunofficialcoder 274 862 3ms 21 Jan 2024 647th plcc0 274 862 3ms 10 Apr 2025 647th HumanoidCPU 274 862 3ms 4 Aug 2025 650th robin-scragg 273 313 17ms 6 Jun 2025 651st JOrE20 273 391 43ms 18 Feb 2026 652nd MeWhenI 🇻🇦 273 866 3ms 1 Sep 2023 653rd Mabeloid 🇳🇴 272 232 1ms 15 Oct 2025 654th KatieLG 🇬🇧 272 867 3ms 2 Sep 2023 654th KatieLG-Transpiler 🇬🇧 272 867 3ms 2 Sep 2023 656th crizin 🇰🇷 269 534 434ms 15 Sep 2023 657th Yewzir 🇧🇪 269 593 1,880ms 14 Nov 2025 658th HumanoidCPU 268 311 401ms 12 Nov 2025 659th bac0id 267 236 2ms 8 Jan 2025 660th Jacob385 267 538 478ms 4 Aug 2024 661st msbranicky 267 590 2,757ms 11 Jan 2025 662nd JOrE20 267 768 4ms 29 Jan 2026 663rd InigoK 🇺🇸 267 883 3ms 6 Aug 2025 664th trinityy-7 266 237 1ms 10 Oct 2023 665th KatieLG 🇬🇧 266 769 3ms 11 Aug 2024 665th Shanethegamer 🇺🇸 266 769 3ms 11 Aug 2024 665th HumanoidCPU 266 769 3ms 13 Aug 2024 665th KatieLG-Transpiler 🇬🇧 266 769 3ms 16 Aug 2024 665th Mabeloid 🇳🇴 266 769 4ms 21 Sep 2024 665th CaedenHarper 🇨🇦 266 769 3ms 22 Jan 2025 665th snoozingnewt 🇨🇦 266 769 3ms 28 Sep 2025 672nd peachey2k2 262 240 2ms 22 Nov 2025 673rd msbranicky 262 638 150ms 1 Sep 2023 674th c0d3-4-F00d 🇩🇪 261 241 2ms 4 Dec 2023 675th helbling 🇨🇭 260 242 1ms 25 Jul 2024 676th Shanethegamer 🇺🇸 260 781 22ms 1 Sep 2023 676th KatieLG 🇬🇧 260 781 23ms 2 Sep 2023 676th KatieLG-Transpiler 🇬🇧 260 781 22ms 2 Sep 2023 676th snoozingnewt 🇨🇦 260 781 22ms 5 Sep 2023 676th vgamula 🇺🇦 260 781 22ms 6 Sep 2023 676th HumanoidCPU 260 781 22ms 16 Apr 2024 676th Mabeloid 🇳🇴 260 781 22ms 21 Sep 2024 676th dokutan 260 781 22ms 18 Oct 2024 676th CaedenHarper 🇨🇦 260 781 23ms 22 Jan 2025 685th ndren 260 782 25ms 20 Jan 2025 685th Stockoh 🇫🇷 260 782 23ms 9 Jan 2026 687th Martymoose98 258 244 1ms 30 May 2025 687th prestosilver 🇺🇸 258 244 2ms 6 days ago 689th tomtheisen 🇺🇸 258 521 416ms 13 Feb 2025 690th dokutan 257 652 115ms 29 Dec 2025 691st JunkIce 253 338 10ms 13 Feb 2025 692nd KatieLG 🇬🇧 251 712 3ms 22 Aug 2024 693rd 1231234md5 🇨🇳 249 344 17ms 12 Dec 2023 694th blaztoma 🇱🇹 249 540 418ms 6 Sep 2025 695th gigaprofisi 🇺🇸 248 254 2ms 16 Jul 2025 696th JOrE20 248 327 27ms 21 Feb 2026 697th dokutan 247 305 35ms 13 Mar 2025 698th JunkIce 247 338 438ms 13 Feb 2025 699th rak1507 🇬🇧 246 347 49ms 1 Sep 2023 700th kallmi28 🇨🇿 244 258 2ms 8 Nov 2023 701st dokutan 244 588 361ms 24 Sep 2025 702nd dokutan 244 791 122ms 18 Oct 2024 703rd MeWhenI 🇻🇦 243 779 8ms 1 Sep 2023 703rd Shanethegamer 🇺🇸 243 779 9ms 1 Sep 2023 703rd HumanoidCPU 243 779 9ms 16 Apr 2024 703rd Mabeloid 🇳🇴 243 779 9ms 21 Sep 2024 703rd dokutan 243 779 9ms 18 Oct 2024 703rd CaedenHarper 🇨🇦 243 779 10ms 22 Jan 2025 709th Shanethegamer 🇺🇸 243 795 109ms 1 Sep 2023 709th KatieLG 🇬🇧 243 795 114ms 2 Sep 2023 709th KatieLG-Transpiler 🇬🇧 243 795 109ms 2 Sep 2023 709th msbranicky 243 795 111ms 11 Sep 2023 709th HumanoidCPU 243 795 104ms 16 Apr 2024 709th Mabeloid 🇳🇴 243 795 123ms 21 Sep 2024 709th CaedenHarper 🇨🇦 243 795 109ms 21 Jan 2025 709th JOrE20 243 795 118ms 10 Feb 2026 717th yzhs 🇩🇪 242 260 1ms 24 Mar 2024 718th msbranicky 242 596 2ms 10 Oct 2023 719th msbranicky 242 637 6ms 1 Sep 2023 720th snoozingnewt 🇨🇦 242 798 105ms 4 Sep 2023 First Prev 641–720 of 1,413 Next Last