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?
Catalan Numbers 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 141st randolchance 957 41 10ms 19 Jan 2023 141st DialFrost 🇸🇬 957 41 11ms 23 Jan 2023 141st prplz 🇦🇺 957 41 9ms 26 Jan 2023 141st sean-niemann 🇺🇸 957 41 10ms 26 Jan 2023 141st xsot 🇸🇬 957 41 10ms 20 May 2023 141st stefangimmillaro 957 41 10ms 12 Jun 2023 141st Argeento 🇵🇱 957 41 11ms 25 Aug 2023 141st ovs-code 🇩🇪 957 41 9ms 29 Sep 2023 141st lukegustafson 🇺🇸 957 41 10ms 13 Nov 2023 141st helbling 🇨🇭 957 41 10ms 17 May 2024 141st vlpx 🇫🇮 957 41 11ms 18 Jun 2024 141st pardouin 🇫🇷 957 41 11ms 4 Aug 2024 141st emgordon154 957 41 10ms 19 Sep 2024 141st edsrzf 🇳🇿 957 41 14ms 19 Nov 2024 141st fuzzylojik-golf 🇺🇸 957 41 10ms 15 May 2025 141st b-illy 🇬🇧 957 41 10ms 2 Jul 2025 141st Yax42 🇫🇷 957 41 10ms 5 Sep 2025 141st CaedenHarper 🇨🇦 957 41 9ms 30 Oct 2025 141st snoozingnewt 🇨🇦 957 41 10ms 21 Nov 2025 141st Lv0Sys 🇵🇱 957 41 10ms 6 Dec 2025 181st andersk 🇺🇸 953 45 11ms 25 Oct 2022 181st FlorianCassayre 🇫🇷 953 45 9ms 16 Sep 2023 181st Command-Master 953 45 12ms 23 Sep 2023 181st cesarm4 953 45 9ms 29 Nov 2023 181st Natanaelel 🇸🇪 953 45 11ms 3 Jan 2024 181st klixel 🇨🇦 953 45 11ms 18 Nov 2024 187th Lydxn 🇨🇦 951 32 246ms 29 Jan 2022 187th btnlq 951 32 305ms 29 Jan 2022 187th sisyphus-ppcg 🇦🇺 951 32 253ms 2 Feb 2022 190th Lydxn 🇨🇦 945 39 392ms 21 Jan 2024 190th Steffan153 🇫🇮 945 39 410ms 17 Aug 2024 190th sean-niemann 🇺🇸 945 39 418ms 24 Jan 2025 193rd Lydxn 🇨🇦 942 39 221ms 29 Jan 2022 193rd JayXon 🇺🇸 942 39 233ms 29 Jan 2022 193rd HPWiz 🇳🇿 942 39 208ms 30 Jan 2022 193rd antimon2 🇯🇵 942 39 486ms 5 Sep 2022 193rd Steffan153 🇫🇮 942 39 251ms 19 Mar 2023 193rd sisyphus-ppcg 🇦🇺 942 39 178ms 20 Mar 2023 193rd ovs-code 🇩🇪 942 39 199ms 11 Apr 2023 193rd p-zubieta 942 39 521ms 25 Sep 2023 193rd DialFrost 🇸🇬 942 39 189ms 2 Jan 2024 193rd sean-niemann 🇺🇸 942 39 233ms 12 Mar 2025 203rd Shanethegamer 🇺🇸 935 22 35ms 29 Jan 2022 203rd scpchicken 🇵🇼 935 22 35ms 29 Jan 2022 203rd SirBogman 🇺🇸 935 22 34ms 29 Jan 2022 203rd NewDefectus 🇮🇱 935 22 34ms 30 Jan 2022 203rd yzhs 🇩🇪 935 22 33ms 16 Jun 2022 203rd saltysylvi 935 22 33ms 5 Aug 2022 203rd DialFrost 🇸🇬 935 22 31ms 30 Nov 2022 203rd MeWhenI 🇻🇦 935 22 33ms 30 Nov 2022 203rd sean-niemann 🇺🇸 935 22 33ms 4 Jan 2023 203rd Betuaredead 935 22 32ms 21 Jan 2023 203rd Steffan153 🇫🇮 935 22 36ms 28 Jan 2023 203rd ashtraypettingzoo 🇺🇸 935 22 34ms 23 Feb 2023 203rd Yewzir 🇧🇪 935 22 32ms 6 Nov 2023 203rd jitwit 935 22 32ms 10 May 2025 203rd eprovst 🇧🇪 935 22 34ms 16 Sep 2025 218th Lydxn 🇨🇦 935 38 28ms 7 Jul 2023 219th lynn 935 49 124ms 29 Jan 2022 219th Lydxn 🇨🇦 935 49 129ms 29 Jan 2022 219th JayXon 🇺🇸 935 49 126ms 29 Jan 2022 219th annaproxy 935 49 123ms 29 Jan 2022 219th rak1507 🇬🇧 935 49 124ms 29 Jan 2022 219th HPWiz 🇳🇿 935 49 124ms 29 Jan 2022 219th xnor-gate 935 49 127ms 30 Jan 2022 219th arjanadriaanse 🇳🇱 935 49 123ms 9 Feb 2022 219th ovs-code 🇩🇪 935 49 125ms 6 Mar 2022 219th GrayJoKing 🇦🇺 935 49 124ms 10 Mar 2022 219th Sakisan 🇧🇪 935 49 126ms 7 Apr 2022 219th Steffan153 🇫🇮 935 49 127ms 24 Sep 2022 219th btnlq 935 49 125ms 17 Oct 2023 219th Natanaelel 🇸🇪 935 49 124ms 3 Jan 2024 219th DialFrost 🇸🇬 935 49 120ms 5 Aug 2024 219th pardouin 🇫🇷 935 49 122ms 8 Oct 2024 219th error256 935 49 128ms 26 Oct 2024 219th sean-niemann 🇺🇸 935 49 131ms 30 Dec 2024 219th fuzzylojik-golf 🇺🇸 935 49 121ms 14 Sep 2025 219th edsrzf 🇳🇿 935 49 133ms 21 Dec 2025 239th lifthrasiir 🇰🇷 934 42 10ms 23 Nov 2024 240th btjones0 932 46 9ms 6 Feb 2022 First Prev 161–240 of 2,051 Next Last