The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 3 days. Why not try and solve them ahead of time?
Catalan Numbers 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 879th dokutan 766 2,879 3ms 6 days ago 882nd HumanoidCPU 766 2,880 3ms 1 Jan 2026 882nd KatieLG 🇬🇧 766 2,880 4ms 21 Feb 2026 884th petroselo 765 56 9ms 12 Apr 2022 884th HumanoidCPU 765 56 17ms 27 May 2024 884th kevinnaviapaiva 765 56 10ms 19 Dec 2024 884th wobblybits 765 56 10ms 19 Aug 2025 888th brimstonetrader 764 60 125ms 10 Jan 2024 888th YAJUE114514 764 60 138ms 23 Jul 2025 890th Yewzir 🇧🇪 763 102 217ms 7 May 2024 891st primo-ppcg 🇹🇭 763 132 3ms 14 Nov 2022 892nd LeeCamp 762 27 33ms 10 Feb 2022 893rd snoozingnewt 🇨🇦 762 154 306ms 29 Oct 2025 894th pardouin 🇫🇷 760 51 62ms 13 Sep 2024 895th Stockoh 🇫🇷 758 51 404ms 23 Jun 2024 896th DialFrost 🇸🇬 757 164 121ms 15 Dec 2025 897th SirBogman 🇺🇸 756 26 41ms 10 Sep 2022 897th Herbert00709 🇵🇱 756 26 39ms 21 Feb 2024 899th SirFireball3521 755 52 10ms 3 Nov 2022 899th albanian-laundromat 755 52 11ms 24 Nov 2025 901st ovs-code 🇩🇪 752 32 145ms 29 Dec 2023 901st Steffan153 🇫🇮 752 32 110ms 11 Mar 2024 903rd iczelia 🇩🇪 752 52 29ms 14 Oct 2025 904th Terobero 752 57 11ms 21 Aug 2024 904th Mick-Travis 752 57 12ms 8 Dec 2024 906th pardouin 🇫🇷 752 84 129ms 8 Mar 2025 907th MeWhenI 🇻🇦 752 156 307ms 10 Feb 2023 908th Jeremy-Stafford 751 61 124ms 28 Feb 2023 908th inverseLorentz 🇦🇺 751 61 124ms 23 Apr 2024 910th dokutan 751 66 1,236ms 26 Feb 2026 911th pardouin 🇫🇷 750 68 6ms 26 Apr 2025 912th MeWhenI 🇻🇦 749 219 140ms 16 Aug 2024 913th snoozingnewt 🇨🇦 747 47 946ms 21 Nov 2025 914th Alex-x90 🇺🇸 747 147 559ms 6 May 2024 915th ovs-code 🇩🇪 747 161 134ms 21 Apr 2025 916th MeWhenI 🇻🇦 746 60 9ms 29 Jan 2022 917th Shanethegamer 🇺🇸 744 85 112ms 14 Oct 2022 917th edsrzf 🇳🇿 744 85 113ms 30 Apr 2025 919th KasperKivimaeki 🇫🇮 744 154 2ms 3 Sep 2025 920th nipzu 742 162 141ms 2 Apr 2024 921st dpinchbe 735 28 33ms 6 Sep 2024 922nd edsrzf 🇳🇿 734 289 42ms 11 Feb 2026 923rd Waffle3z 733 189 2ms 29 Jan 2022 924th madex 🇩🇪 731 42 34ms 12 days ago 925th MeWhenI 🇻🇦 731 53 65ms 5 Apr 2025 926th HumanoidCPU 730 53 452ms 27 May 2024 926th Mabeloid 🇳🇴 730 53 416ms 21 Sep 2024 928th ovs-code 🇩🇪 729 70 8ms 11 Dec 2023 928th DialFrost 🇸🇬 729 70 6ms 1 Jan 2026 928th dokutan 729 70 3ms 26 Feb 2026 931st CaedenHarper 🇨🇦 729 161 306ms 20 Nov 2025 932nd madex 🇩🇪 728 68 1,303ms 12 days ago 933rd dvargas46 🇺🇸 728 158 829ms 5 Feb 2023 934th iczelia 🇩🇪 727 54 13ms 14 Oct 2025 935th Shanethegamer 🇺🇸 725 73 5ms 4 Oct 2024 936th snoozingnewt 🇨🇦 725 164 95ms 8 Feb 2026 937th shellbertt 🇨🇦 724 52 216ms 19 Mar 2023 937th davbass 🇮🇹 724 52 248ms 22 Aug 2023 939th h3ra993huskp 🇯🇵 723 150 429ms 30 Nov 2025 940th emgordon154 720 163 291ms 18 Jan 2025 941st primo-ppcg 🇹🇭 719 160 73ms 4 Feb 2023 942nd msbranicky 716 54 440ms 17 Jan 2024 943rd Irratix 🇳🇱 716 64 125ms 29 Jan 2022 944th msbranicky 715 164 296ms 31 Aug 2023 945th snoozingnewt 🇨🇦 714 43 38ms 26 Sep 2025 946th LeeCamp 714 60 10ms 9 Feb 2022 946th guilhem-roy 🇫🇷 714 60 10ms 22 Feb 2022 946th Eilonlif 🇮🇱 714 60 10ms 27 Aug 2022 946th LogicalJoe 714 60 10ms 18 Sep 2022 946th 5quiwyrm 714 60 10ms 22 Oct 2022 946th TaserTheFox 🇺🇸 714 60 9ms 9 Jan 2023 946th ljweel 714 60 10ms 13 Feb 2023 946th shellbertt 🇨🇦 714 60 10ms 27 Apr 2023 946th ssbhatt4321 714 60 10ms 11 Jun 2023 946th 2011-Chan-Ethan 714 60 9ms 14 Jul 2023 946th PeterTillema 🇳🇱 714 60 10ms 10 Oct 2023 946th kurkale6ka 714 60 9ms 21 Dec 2023 946th sultan 714 60 9ms 3 Mar 2024 946th cuboids 714 60 10ms 10 Jul 2024 946th jatloe 714 60 10ms 27 Sep 2024 First Prev 881–960 of 2,066 Next Last