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?
Tower of Hanoi 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 801st duckyluuk 🇳🇱 672 66 12ms 30 Oct 2025 801st helbling 🇨🇭 672 66 13ms 12 Dec 2025 801st JOrE20 672 66 10ms 28 Jan 2026 804th firegene 🇮🇪 672 75 11ms 20 Feb 2026 805th Stockoh 🇫🇷 671 113 28ms 9 Jan 2026 806th BREMAUCY 🇫🇷 670 74 474ms 1 Dec 2025 806th JOrE20 670 74 441ms 7 Jan 2026 806th KrausRaus 🇺🇸 670 74 5ms 26 days ago 809th Yewzir 🇧🇪 670 92 2,466ms 30 Nov 2025 810th elgan65536 🇺🇸 670 98 133ms 7 Feb 2026 811th bitsandbeyond 🇳🇱 669 119 121ms 31 Oct 2025 812th Ripick 663 76 11ms 14 Nov 2025 812th LostSyntax21 🇬🇧 663 76 12ms 30 Nov 2025 812th scpchicken 🇵🇼 663 76 12ms 5 Dec 2025 815th msbranicky 663 93 2,598ms 4 Dec 2025 816th acotis 663 99 120ms 2 Jan 2026 817th CaedenHarper 🇨🇦 662 157 1,890ms 30 Nov 2025 818th GolfingSuccess 🇬🇷 661 49 3ms 4 Nov 2025 819th Shanethegamer 🇺🇸 659 102 116ms 2 Nov 2025 820th bitsandbeyond 🇳🇱 656 75 148ms 5 Nov 2025 821st mousetail 🇳🇱 655 77 12ms 23 Nov 2025 822nd madex 🇩🇪 654 74 774ms 13 days ago 823rd Yewzir 🇧🇪 654 116 28ms 30 Nov 2025 824th scpchicken 🇵🇼 652 76 478ms 1 Jan 2026 825th AutumnWind75 652 119 438ms 10 Dec 2025 826th GolfingSuccess 🇬🇷 651 157 1,459ms 7 Dec 2025 827th emgordon154 650 92 7ms 24 days ago 828th AlephSquirrel 648 105 9ms 30 Nov 2025 829th madex 🇩🇪 647 129 269ms 13 days ago 830th Bmrl7 646 78 11ms 20 Dec 2025 831st tomh1012 644 77 435ms 26 days ago 832nd jameswmccarty 643 96 2,542ms 8 Feb 2026 833rd scpchicken 🇵🇼 643 100 10ms 14 days ago 834th HumanoidCPU 643 111 108ms 30 Nov 2025 835th GolfingSuccess 🇬🇷 639 72 1ms 30 Oct 2025 836th msbranicky 638 79 11ms 26 Nov 2025 836th nemoyatpeace 638 79 16ms 28 Dec 2025 836th nstearns96 🇬🇧 638 79 11ms 31 Dec 2025 836th tomh1012 638 79 10ms 26 days ago 836th Andrey2001 638 79 11ms 5 days ago 841st dokutan 638 163 1,613ms 5 Dec 2025 842nd HumanoidCPU 637 111 457ms 29 Nov 2025 843rd msbranicky 637 131 303ms 4 Dec 2025 844th Herbert00709 🇵🇱 636 78 5ms 24 days ago 845th BREMAUCY 🇫🇷 636 97 2,505ms 3 Dec 2025 846th HumanoidCPU 636 122 57ms 29 Nov 2025 847th a6166231 🇨🇳 634 70 11ms 12 Feb 2026 848th bitsandbeyond 🇳🇱 634 99 3ms 3 Jan 2026 849th D-MOVE 🇵🇭 632 71 42ms 22 days ago 850th prestosilver 🇺🇸 632 97 2ms 3 Dec 2025 851st scpchicken 🇵🇼 632 132 267ms 14 days ago 852nd madex 🇩🇪 631 102 10ms 13 days ago 853rd aksyristos 631 123 60ms 3 Dec 2025 853rd yeminghan2021 631 123 63ms 3 Feb 2026 855th stackofbears 630 62 34ms 22 Dec 2025 856th dokutan 630 95 7ms 25 Feb 2026 857th msbranicky 630 108 8ms 4 Dec 2025 858th jameswmccarty 628 77 716ms 8 Feb 2026 859th msbranicky 628 79 457ms 3 Dec 2025 859th madex 🇩🇪 628 79 447ms 13 days ago 859th Andrey2001 628 79 461ms 5 days ago 862nd rucin93 🇵🇱 627 64 54ms 30 Oct 2025 863rd HumanoidCPU 626 105 114ms 29 Nov 2025 864th alexsave 625 71 10ms 30 Nov 2025 865th Waffle3z 622 87 2ms 26 Dec 2025 865th Andriamanitra 🇫🇮 622 87 2ms 26 days ago 867th HumanoidCPU 621 85 91ms 29 Nov 2025 868th tomh1012 620 78 779ms 26 days ago 869th IISResetMe 619 78 343ms 30 Nov 2025 870th MeWhenI 🇻🇦 618 76 5ms 23 Nov 2025 871st HumanoidCPU 616 72 12ms 29 Nov 2025 871st olleicua 🇺🇸 616 72 10ms 8 Dec 2025 873rd JOrE20 614 102 43ms 28 Nov 2025 874th MeWhenI 🇻🇦 613 104 1,025ms 23 Nov 2025 875th HumanoidCPU 612 121 478ms 30 Nov 2025 876th AlephSquirrel 611 79 304ms 30 Nov 2025 877th kmathis22 611 101 2,374ms 8 days ago 878th AstroOrbis 610 117 94ms 26 days ago 879th madeforlosers 608 73 10ms 11 days ago 880th RDShah 607 83 11ms 1 Dec 2025 First Prev 801–880 of 1,478 Next Last