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?
Tutorial 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 780th CaedenHarper 🇨🇦 0 61 12ms 3 Feb 2025 780th BalaM314 0 61 16ms 4 Feb 2025 780th kg583 🇺🇸 0 61 77ms 5 Feb 2025 780th GolfingSuccess 🇬🇷 0 61 69ms 5 Feb 2025 780th targrik 0 61 12ms 8 Feb 2025 780th MeWhenI 🇻🇦 0 61 3ms 14 Feb 2025 780th targrik 0 61 3ms 15 Feb 2025 780th attila8192 0 61 14ms 1 Mar 2025 780th targrik 0 61 2ms 14 Mar 2025 780th janlelis 0 61 15ms 31 Mar 2025 780th b-illy 🇬🇧 0 61 18ms 16 Apr 2025 780th janbehrens 🇩🇪 0 61 14ms 17 Apr 2025 780th pardouin 🇫🇷 0 61 19ms 17 Apr 2025 780th Shanethegamer 🇺🇸 0 61 81ms 17 Apr 2025 780th edsrzf 🇳🇿 0 61 13ms 17 Apr 2025 780th HumanoidCPU 0 61 76ms 18 Apr 2025 780th HumanoidCPU 0 61 12ms 18 Apr 2025 780th AlephSquirrel 0 61 13ms 20 Apr 2025 780th Sam-Vrgl 0 61 16ms 13 May 2025 780th c-py 0 61 13ms 14 May 2025 780th albanian-laundromat 0 61 76ms 6 Jun 2025 780th Andrey-Plotnikov 0 61 13ms 19 Jun 2025 780th a6166231 🇨🇳 0 61 13ms 20 Jun 2025 780th elana-teal 0 61 11ms 20 Jun 2025 780th BREMAUCY 🇫🇷 0 61 12ms 1 Jul 2025 780th RYSF13 🇨🇳 0 61 13ms 5 Jul 2025 780th p01 0 61 13ms 28 Jul 2025 780th KrausRaus 🇺🇸 0 61 14ms 29 Jul 2025 780th dmrichwa 🇺🇸 0 61 15ms 29 Jul 2025 780th dokutan 0 61 2ms 5 Aug 2025 780th gitchaell 🇧🇴 0 61 15ms 6 Aug 2025 780th lukepolak 0 61 15ms 7 Aug 2025 780th adrianbgo 0 61 14ms 7 Aug 2025 780th helbling 🇨🇭 0 61 14ms 28 Aug 2025 780th snoozingnewt 🇨🇦 0 61 75ms 15 Sep 2025 780th snoozingnewt 🇨🇦 0 61 14ms 15 Sep 2025 780th larsendaniel 0 61 16ms 7 Nov 2025 780th JOrE20 0 61 14ms 18 Nov 2025 780th GodlyProgrammer1 0 61 14ms 22 Nov 2025 780th Kacarott 🇦🇺 0 61 104ms 25 Nov 2025 780th egertaia 0 61 13ms 9 Jan 2026 780th r58iiz 0 61 15ms 15 Jan 2026 780th ragonscreen 0 61 14ms 16 Jan 2026 780th matzuka 0 61 39ms 29 Jan 2026 780th FoxInTheClouds 0 61 14ms 5 Feb 2026 780th Ultra814 0 61 13ms 19 Feb 2026 780th weliveinhell 🇭🇹 0 61 14ms 13 days ago 780th marcuswilcour 0 61 12ms 4 hours ago 849th emgordon154 0 62 2ms 27 Nov 2024 849th CLOStrophobic 🇮🇹 0 62 3ms 4 Feb 2025 849th DialFrost 🇸🇬 0 62 11ms 15 Feb 2025 849th heanyang1 0 62 14ms 26 Mar 2025 849th dokutan 0 62 1,721ms 15 Jul 2025 849th 6512345 0 62 161ms 4 Nov 2025 855th kg583 🇺🇸 0 63 49ms 21 Nov 2024 855th sean-niemann 🇺🇸 0 63 162ms 10 Dec 2024 855th MeWhenI 🇻🇦 0 63 6ms 18 Dec 2024 855th zacjl 0 63 52ms 31 Dec 2024 855th CLOStrophobic 🇮🇹 0 63 58ms 17 Jan 2025 855th edsrzf 🇳🇿 0 63 50ms 9 Feb 2025 855th GolfingSuccess 🇬🇷 0 63 49ms 9 Feb 2025 855th Nemikolh 🇫🇷 0 63 16ms 12 Feb 2025 855th GolfingSuccess 🇬🇷 0 63 189ms 20 Feb 2025 855th varhammer 0 63 6ms 22 Feb 2025 855th voytxt 🇨🇿 0 63 189ms 17 Apr 2025 855th FlyingPenguin223 0 63 51ms 17 Apr 2025 855th DialFrost 🇸🇬 0 63 185ms 17 Apr 2025 855th DialFrost 🇸🇬 0 63 5ms 17 Apr 2025 855th DialFrost 🇸🇬 0 63 49ms 17 Apr 2025 855th pardouin 🇫🇷 0 63 176ms 17 Apr 2025 855th Shanethegamer 🇺🇸 0 63 5ms 17 Apr 2025 855th Shanethegamer 🇺🇸 0 63 54ms 17 Apr 2025 855th GolfingSuccess 🇬🇷 0 63 6ms 17 Apr 2025 855th HumanoidCPU 0 63 177ms 18 Apr 2025 855th HumanoidCPU 0 63 7ms 18 Apr 2025 855th HumanoidCPU 0 63 50ms 18 Apr 2025 855th CaedenHarper 🇨🇦 0 63 163ms 18 Apr 2025 855th CaedenHarper 🇨🇦 0 63 6ms 18 Apr 2025 855th CaedenHarper 🇨🇦 0 63 56ms 18 Apr 2025 855th dokutan 0 63 6ms 28 Apr 2025 First Prev 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