The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 28 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 721st MeWhenI 🇻🇦 729 51 5ms 23 Nov 2025 722nd albanian-laundromat 727 61 13ms 24 Nov 2025 723rd albanian-laundromat 727 75 127ms 25 Nov 2025 724th AlephSquirrel 726 85 2,669ms 30 Nov 2025 725th GolfingSuccess 🇬🇷 726 99 9ms 5 Nov 2025 726th MeWhenI 🇻🇦 725 141 1,436ms 3 Dec 2025 727th bitsandbeyond 🇳🇱 723 73 89ms 2 Nov 2025 728th HumanoidCPU 721 85 2ms 29 Nov 2025 729th plcc0 718 69 5ms 26 days ago 730th rucin93 🇵🇱 717 68 1ms 30 Oct 2025 731st albanian-laundromat 717 87 433ms 30 Nov 2025 732nd emplv 🇱🇻 715 62 12ms 30 Oct 2025 732nd Lv0Sys 🇵🇱 715 62 10ms 21 Feb 2026 734th Yewzir 🇧🇪 714 94 11ms 30 Nov 2025 735th aksyristos 713 86 2ms 27 days ago 736th CaedenHarper 🇨🇦 713 88 88ms 30 Nov 2025 737th MeWhenI 🇻🇦 713 98 42ms 24 Nov 2025 738th anter69 🇭🇺 712 63 35ms 5 Dec 2025 739th tomh1012 710 108 9ms 12 Feb 2026 740th albanian-laundromat 709 107 25ms 30 Oct 2025 740th HumanoidCPU 709 107 28ms 1 Dec 2025 740th Natanaelel 🇸🇪 709 107 24ms 25 Dec 2025 743rd cros107 🇦🇺 707 70 12ms 11 Nov 2025 743rd CutSandstone 707 70 12ms 4 Dec 2025 743rd jameswmccarty 707 70 12ms 3 Jan 2026 743rd zgialor-lab 707 70 12ms 1 Feb 2026 743rd btjones0 707 70 11ms 16 Feb 2026 743rd bzijlema 🇳🇱 707 70 12ms 26 Feb 2026 749th albanian-laundromat 707 90 3ms 14 Dec 2025 750th tomh1012 707 95 11ms 12 Feb 2026 750th madex 🇩🇪 707 95 8ms 15 days ago 752nd BREMAUCY 🇫🇷 705 104 66ms 2 Dec 2025 753rd Yewzir 🇧🇪 704 102 9ms 30 Nov 2025 754th albanian-laundromat 700 111 2,534ms 23 Nov 2025 755th emgordon154 698 71 5ms 2 Mar 2026 756th albanian-laundromat 696 86 112ms 23 Nov 2025 757th zgialor-lab 696 88 2ms 16 Dec 2025 757th jgbaldwinbrown 696 88 2ms 15 Jan 2026 759th madex 🇩🇪 693 64 9ms 14 days ago 760th bitsandbeyond 🇳🇱 691 68 4ms 1 Nov 2025 761st HumanoidCPU 691 101 44ms 30 Nov 2025 762nd dokutan 689 72 5ms 28 Nov 2025 763rd albanian-laundromat 689 73 83ms 24 Nov 2025 764th D-MOVE 🇵🇭 686 117 26ms 4 Feb 2026 764th JOrE20 686 117 25ms 9 Feb 2026 766th ndren 685 79 2ms 24 days ago 767th GolfingSuccess 🇬🇷 685 98 9ms 30 Nov 2025 768th bitsandbeyond 🇳🇱 684 94 10ms 31 Dec 2025 769th Yewzir 🇧🇪 684 122 300ms 30 Nov 2025 769th D-MOVE 🇵🇭 684 122 269ms 16 Feb 2026 769th prestosilver 🇺🇸 684 122 288ms 27 days ago 772nd jkelly467 682 92 91ms 2 Mar 2026 773rd HumanoidCPU 680 88 109ms 30 Nov 2025 774th albanian-laundromat 679 99 117ms 30 Oct 2025 775th ahmetdemirag 🇨🇾 678 73 11ms 28 Nov 2025 775th SirBogman 🇺🇸 678 73 11ms 1 Dec 2025 775th csharpython 678 73 11ms 6 Jan 2026 775th themoonisacheese 678 73 11ms 23 Jan 2026 779th BREMAUCY 🇫🇷 678 99 8ms 2 Dec 2025 779th Schmitt-Very-Cool 678 99 7ms 6 Dec 2025 781st jameswmccarty 678 123 287ms 8 Feb 2026 782nd YAJUE114514 676 80 2ms 24 days ago 783rd Shanethegamer 🇺🇸 674 93 91ms 2 Nov 2025 784th TheZwierzLF 🇵🇱 673 71 469ms 12 Dec 2025 785th Jacob385 673 105 450ms 10 Nov 2025 786th CaedenHarper 🇨🇦 673 117 118ms 30 Nov 2025 787th duckyluuk 🇳🇱 672 66 12ms 30 Oct 2025 787th helbling 🇨🇭 672 66 13ms 12 Dec 2025 787th JOrE20 672 66 10ms 28 Jan 2026 790th Stockoh 🇫🇷 671 113 28ms 9 Jan 2026 791st KrausRaus 🇺🇸 670 74 5ms 2 Mar 2026 792nd Yewzir 🇧🇪 670 92 2,466ms 30 Nov 2025 793rd elgan65536 🇺🇸 670 98 133ms 7 Feb 2026 794th Babafaba 669 74 13ms 21 Nov 2025 794th TheZwierzLF 🇵🇱 669 74 11ms 29 Nov 2025 794th BREMAUCY 🇫🇷 669 74 11ms 30 Nov 2025 794th RandGuy 669 74 11ms 2 Dec 2025 794th annaproxy 669 74 11ms 2 Dec 2025 794th aksyristos 669 74 11ms 3 Dec 2025 794th hippalectryon-0 669 74 12ms 6 Dec 2025 First Prev 721–800 of 1,465 Next Last