The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 42 hours. Why not try and solve them ahead of time?
Tower of Hanoi 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 481st MeWhenI 🇻🇦 855 70 112ms 23 Nov 2025 482nd Shanethegamer 🇺🇸 855 73 391ms 4 Nov 2025 482nd MeWhenI 🇻🇦 855 73 453ms 21 Nov 2025 482nd CaedenHarper 🇨🇦 855 73 381ms 29 Nov 2025 485th GolfingSuccess 🇬🇷 854 51 144ms 3 Nov 2025 485th Steffan153 🇫🇮 854 51 149ms 27 days ago 487th Shanethegamer 🇺🇸 853 52 10ms 4 Nov 2025 487th MeWhenI 🇻🇦 853 52 11ms 21 Nov 2025 487th CaedenHarper 🇨🇦 853 52 11ms 29 Nov 2025 490th AlephSquirrel 853 56 383ms 30 Oct 2025 490th MeWhenI 🇻🇦 853 56 471ms 23 Nov 2025 490th CaedenHarper 🇨🇦 853 56 527ms 29 Nov 2025 490th Kacarott 🇦🇺 853 56 470ms 30 Nov 2025 494th Shanethegamer 🇺🇸 852 66 1,303ms 3 Nov 2025 495th h3ra993huskp 🇯🇵 852 83 447ms 14 Dec 2025 496th MeWhenI 🇻🇦 852 89 27ms 24 Nov 2025 497th dokutan 851 72 2ms 8 days ago 498th Natanaelel 🇸🇪 849 46 33ms 8 Nov 2025 499th emgordon154 849 57 926ms 21 Dec 2025 500th MeWhenI 🇻🇦 849 70 4ms 24 Nov 2025 501st Natanaelel 🇸🇪 847 53 36ms 4 Nov 2025 502nd ovs-code 🇩🇪 847 76 14ms 3 Nov 2025 503rd edsrzf 🇳🇿 846 93 108ms 1 Dec 2025 504th dokutan 844 92 64ms 24 Nov 2025 505th arcpolaris 843 74 399ms 3 Dec 2025 506th Shanethegamer 🇺🇸 843 91 8ms 3 Nov 2025 506th MeWhenI 🇻🇦 843 91 8ms 23 Nov 2025 508th dokutan 842 78 130ms 1 Dec 2025 509th bitsandbeyond 🇳🇱 842 90 27ms 2 Nov 2025 510th MeWhenI 🇻🇦 842 99 295ms 23 Nov 2025 511th ethanlally 841 84 574ms 23 Nov 2025 511th dokutan 841 84 492ms 28 Nov 2025 511th jkelly467 841 84 469ms 2 Dec 2025 514th MeWhenI 🇻🇦 840 54 1,213ms 23 Nov 2025 514th emgordon154 840 54 1,250ms 20 Dec 2025 516th KasperKivimaeki 🇫🇮 840 59 5ms 27 days ago 516th namelessiw 840 59 5ms 27 days ago 516th Lv0Sys 🇵🇱 840 59 5ms 23 days ago 519th sean-niemann 🇺🇸 840 67 1,246ms 2 Dec 2025 520th Shanethegamer 🇺🇸 840 68 3ms 4 Nov 2025 520th MeWhenI 🇻🇦 840 68 3ms 23 Nov 2025 520th DialFrost 🇸🇬 840 68 3ms 3 Dec 2025 523rd madex 🇩🇪 840 73 2ms 14 days ago 524th edsrzf 🇳🇿 840 80 123ms 9 days ago 525th rucin93 🇵🇱 839 56 5ms 30 Oct 2025 525th DialFrost 🇸🇬 839 56 57ms 29 Dec 2025 527th davecame 839 59 12ms 13 Nov 2025 527th Kacarott 🇦🇺 839 59 12ms 15 Nov 2025 527th commandz0 🇺🇸 839 59 12ms 28 Nov 2025 527th YAJUE114514 839 59 12ms 10 Dec 2025 527th andrewjc2000 839 59 11ms 7 Jan 2026 527th TheSecondComing123 839 59 12ms 4 Feb 2026 533rd bitsandbeyond 🇳🇱 838 52 145ms 1 Nov 2025 534th edsrzf 🇳🇿 838 57 444ms 1 Dec 2025 534th Natanaelel 🇸🇪 838 57 443ms 25 Dec 2025 536th edsrzf 🇳🇿 838 76 4ms 9 days ago 537th snoozingnewt 🇨🇦 837 53 11ms 28 Nov 2025 537th Yax42 🇫🇷 837 53 10ms 2 Dec 2025 539th GolfingSuccess 🇬🇷 837 94 111ms 28 Nov 2025 539th DialFrost 🇸🇬 837 94 103ms 3 Dec 2025 541st CaedenHarper 🇨🇦 836 75 39ms 30 Nov 2025 542nd jkelly467 835 102 2ms 2 Dec 2025 543rd DialFrost 🇸🇬 834 59 149ms 2 Dec 2025 544th kg583 🇺🇸 834 92 9ms 30 Oct 2025 545th plcc0 833 91 27ms 25 days ago 546th NickTheEASDude 🇺🇸 832 65 2ms 24 days ago 547th bitsandbeyond 🇳🇱 832 89 470ms 2 Nov 2025 548th Shanethegamer 🇺🇸 831 54 32ms 3 Nov 2025 548th blaztoma 🇱🇹 831 54 34ms 30 Nov 2025 548th fuzzylojik-golf 🇺🇸 831 54 35ms 22 days ago 551st GolfingSuccess 🇬🇷 831 84 39ms 3 Nov 2025 552nd Natanaelel 🇸🇪 829 81 120ms 27 Nov 2025 552nd error256 829 81 11ms 27 days ago 554th sean-niemann 🇺🇸 829 95 117ms 4 Jan 2026 555th fuzzylojik-golf 🇺🇸 827 59 2ms 18 days ago 556th fuzzylojik-golf 🇺🇸 827 68 1,237ms 17 days ago 557th albanian-laundromat 827 220 12ms 5 Dec 2025 558th blaztoma 🇱🇹 826 60 5ms 30 Nov 2025 559th blaztoma 🇱🇹 826 101 273ms 1 Dec 2025 560th Shanethegamer 🇺🇸 825 55 1,318ms 4 Nov 2025 First Prev 481–560 of 1,465 Next Last