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 721st MeWhenI 🇻🇦 241 800 109ms 1 Sep 2023 722nd HumanoidCPU 240 425 862ms 27 Dec 2025 723rd KatieLG 🇬🇧 239 430 10ms 5 Oct 2025 724th msbranicky 238 625 85ms 1 Sep 2023 725th KatieLG 🇬🇧 237 797 9ms 2 Sep 2023 725th KatieLG-Transpiler 🇬🇧 237 797 9ms 2 Sep 2023 727th msbranicky 236 678 1,676ms 17 Sep 2025 728th roguh 🇬🇹 235 268 2ms 23 Jan 2024 729th LostSyntax21 🇬🇧 235 363 35ms 23 Oct 2025 729th Andrey2001 235 363 21ms 3 days ago 731st cbrt-x 235 821 109ms 9 Oct 2023 732nd annaproxy 233 270 2ms 1 Sep 2023 733rd Maximizer02 231 578 5ms 22 Mar 2024 734th retrohun 230 563 2ms 14 days ago 735th msbranicky 230 635 284ms 1 Sep 2023 736th Shanethegamer 🇺🇸 229 448 366ms 1 Sep 2023 737th bac0id 229 587 375ms 9 Jan 2025 738th dokutan 228 569 2ms 6 Jun 2024 739th Shanethegamer 🇺🇸 228 783 2ms 1 Sep 2023 739th theunofficialcoder 228 783 2ms 21 Jan 2024 739th Mabeloid 🇳🇴 228 783 2ms 21 Sep 2024 739th CaedenHarper 🇨🇦 228 783 2ms 22 Jan 2025 743rd alphafalfa 227 572 15ms 1 Aug 2025 744th KatieLG-Transpiler 🇬🇧 227 787 2ms 2 Sep 2023 745th dokutan 226 324 3ms 13 Nov 2024 746th TheZwierzLF 🇵🇱 226 373 2,542ms 7 Dec 2025 747th HumanoidCPU 226 809 6ms 12 Nov 2025 747th dokutan 226 809 6ms 21 Feb 2026 747th CaedenHarper 🇨🇦 226 809 6ms 22 Feb 2026 750th AbhilashaTandon 225 380 17ms 21 Sep 2023 751st msbranicky 223 594 87ms 1 Sep 2023 752nd eiburns 221 285 2ms 6 Nov 2023 753rd dokutan 221 427 150ms 2 Apr 2024 754th KatieLG-Transpiler 🇬🇧 221 802 2ms 2 Sep 2023 755th voytxt 🇨🇿 220 609 417ms 4 Nov 2024 756th dokutan 218 528 12ms 9 Apr 2025 757th msbranicky 218 614 8ms 24 Dec 2023 758th msbranicky 218 617 386ms 8 Sep 2023 759th HumanoidCPU 218 820 2ms 16 Apr 2024 760th Stanbroek 216 291 2ms 18 Sep 2023 761st dokutan 215 624 374ms 5 Jun 2024 762nd KatieLG 🇬🇧 214 854 6ms 21 Feb 2026 763rd msbranicky 212 678 434ms 8 Sep 2023 764th dokutan 212 686 285ms 12 Dec 2025 765th KatieLG 🇬🇧 212 789 124ms 2 Sep 2023 765th Shanethegamer 🇺🇸 212 789 116ms 3 Sep 2023 765th HumanoidCPU 212 789 109ms 27 May 2024 765th RedzGoose 🇦🇺 212 789 114ms 7 Oct 2024 765th CaedenHarper 🇨🇦 212 789 109ms 20 Jan 2025 770th Mabeloid 🇳🇴 211 794 117ms 21 Sep 2024 771st msbranicky 210 590 1ms 28 Sep 2023 772nd TheEric0802 🇩🇪 210 622 3ms 22 Sep 2023 773rd MichalMarsalek 🇨🇿 209 570 127ms 1 Sep 2023 774th MeWhenI 🇻🇦 209 800 119ms 1 Sep 2023 774th gigaprofisi 🇺🇸 209 800 114ms 13 Nov 2025 776th enbyte 206 415 10ms 9 Dec 2023 776th jatloe 206 415 10ms 29 Jan 2024 776th Jacob385 206 415 9ms 18 Apr 2024 779th isaiah0311 🇺🇸 205 308 2ms 30 Jan 2026 780th HumanoidCPU 204 773 2,250ms 24 Oct 2024 780th Shanethegamer 🇺🇸 204 773 2,453ms 24 Oct 2024 780th KatieLG 🇬🇧 204 773 2,316ms 27 Oct 2024 780th CaedenHarper 🇨🇦 204 773 2,269ms 22 Jan 2025 780th Chinay-Domitrix 🇺🇸 204 773 2,239ms 15 Apr 2025 785th msbranicky 202 590 126ms 3 Oct 2023 786th Jacob385 201 415 361ms 18 Apr 2024 787th KatieLG-Transpiler 🇬🇧 201 833 111ms 2 Sep 2023 788th dokutan 199 423 53ms 7 Apr 2024 788th HumanoidCPU 199 423 59ms 17 Apr 2024 790th MeWhenI 🇻🇦 199 776 5ms 1 Sep 2023 790th Shanethegamer 🇺🇸 199 776 5ms 1 Sep 2023 790th KatieLG 🇬🇧 199 776 5ms 2 Sep 2023 790th KatieLG-Transpiler 🇬🇧 199 776 5ms 2 Sep 2023 790th scpchicken 🇵🇼 199 776 5ms 14 Nov 2023 790th HumanoidCPU 199 776 5ms 4 May 2024 790th Mabeloid 🇳🇴 199 776 5ms 21 Sep 2024 790th CaedenHarper 🇨🇦 199 776 5ms 20 Jan 2025 798th snoozingnewt 🇨🇦 198 781 5ms 5 Sep 2023 799th dranjohn 196 437 11ms 11 Sep 2023 800th dokutan 194 542 130ms 6 Nov 2024 First Prev 721–800 of 1,413 Next Last