The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 24 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 881st dokutan 603 104 77ms 23 Jan 2026 882nd HumanoidCPU 601 107 10ms 29 Nov 2025 883rd CaedenHarper 🇨🇦 600 88 90ms 30 Nov 2025 884th bitsandbeyond 🇳🇱 600 99 3ms 3 Jan 2026 885th Natanaelel 🇸🇪 600 139 288ms 25 Dec 2025 886th Nicronmil 599 74 10ms 11 Dec 2025 886th two-bad 🇬🇧 599 74 10ms 17 Dec 2025 888th olleicua 🇺🇸 598 75 34ms 7 Dec 2025 889th JOrE20 597 81 1,108ms 30 Jan 2026 890th anter69 🇭🇺 597 105 84ms 2 Mar 2026 891st CaedenHarper 🇨🇦 596 81 296ms 30 Nov 2025 892nd RDShah 596 83 11ms 1 Dec 2025 893rd KatieLG 🇬🇧 596 108 10ms 30 Nov 2025 894th HumanoidCPU 594 105 378ms 29 Nov 2025 895th Natanaelel 🇸🇪 592 106 122ms 2 Mar 2026 896th BREMAUCY 🇫🇷 592 141 290ms 2 Dec 2025 896th JOrE20 592 141 298ms 30 Jan 2026 898th HumanoidCPU 589 74 145ms 29 Nov 2025 899th anter69 🇭🇺 589 77 1,267ms 5 Dec 2025 900th Yewzir 🇧🇪 589 82 338ms 30 Nov 2025 901st ZakkkkAttackkkk 🇵🇭 589 84 17ms 2 Feb 2026 902nd FortuiteMan 🇫🇷 589 114 11ms 24 Dec 2025 903rd kmathis22 589 120 406ms 25 days ago 904th aksyristos 588 83 1ms 3 Dec 2025 905th SwordF-Official 🇺🇸 588 92 2ms 16 Nov 2025 905th HumanoidCPU 588 92 2ms 29 Nov 2025 905th tomh1012 588 92 2ms 2 Mar 2026 905th prestosilver 🇺🇸 588 92 2ms 2 Mar 2026 905th BREMAUCY 🇫🇷 588 92 2ms 2 Mar 2026 905th m-tkach 🇺🇦 588 92 2ms 2 Mar 2026 911th tomh1012 587 142 283ms 12 Feb 2026 912th Protothor 584 76 10ms 4 Dec 2025 912th Andrey-Plotnikov 584 76 9ms 9 Jan 2026 914th dokutan 583 73 200ms 28 Nov 2025 915th aksyristos 582 93 2ms 27 days ago 916th MeWhenI 🇻🇦 580 111 17ms 28 Nov 2025 917th emgordon154 578 56 4ms 12 days ago 918th Maashau 578 106 2ms 1 Dec 2025 919th kmathis22 576 84 837ms 10 days ago 920th BREMAUCY 🇫🇷 575 78 34ms 1 Dec 2025 921st Schmitt-Very-Cool 575 86 11ms 5 Dec 2025 922nd kmathis22 575 145 278ms 11 days ago 923rd HumanoidCPU 575 181 1,852ms 30 Nov 2025 924th BREMAUCY 🇫🇷 573 109 469ms 1 Dec 2025 925th Schmitt-Very-Cool 573 128 69ms 6 Dec 2025 926th HumanoidCPU 565 111 108ms 30 Nov 2025 927th MeWhenI 🇻🇦 564 74 127ms 24 Nov 2025 928th msbranicky 563 96 2ms 2 Mar 2026 928th Jonson26 563 96 2ms 25 days ago 930th jameswmccarty 561 79 10ms 8 Feb 2026 931st CaedenHarper 🇨🇦 555 121 12ms 30 Nov 2025 932nd bitsandbeyond 🇳🇱 553 107 4ms 16 Nov 2025 933rd IISResetMe 551 90 5ms 2 Mar 2026 934th AstroOrbis 550 122 10ms 12 days ago 935th SirBogman 🇺🇸 549 59 3ms 2 Dec 2025 936th HumanoidCPU 549 88 323ms 30 Nov 2025 937th jameswmccarty 548 129 379ms 31 hours ago 938th dokutan 548 134 692ms 10 Dec 2025 939th matejmatik123 🇸🇰 547 142 1,369ms 16 Jan 2026 940th Yewzir 🇧🇪 545 91 5ms 2 Mar 2026 941st kmathis22 544 91 11ms 11 days ago 942nd Schmitt-Very-Cool 544 130 463ms 1 Dec 2025 943rd emgordon154 541 79 3ms 24 Nov 2025 944th albanian-laundromat 541 104 1,265ms 30 Oct 2025 945th Stockoh 🇫🇷 538 92 11ms 9 Jan 2026 946th scpchicken 🇵🇼 537 125 10ms 1 Jan 2026 947th Matter1024 🇮🇳 536 101 2ms 2 Mar 2026 948th AstroOrbis 536 117 94ms 2 Mar 2026 949th lacrosse 534 84 40ms 29 Nov 2025 950th Schmitt-Very-Cool 534 142 26ms 5 Dec 2025 951st CLOStrophobic 🇮🇹 532 93 10ms 3 Dec 2025 952nd scpchicken 🇵🇼 531 61 2ms 18 days ago 953rd HumanoidCPU 529 95 117ms 29 Nov 2025 954th aksyristos 528 85 36ms 3 Dec 2025 955th tomh1012 527 94 5ms 2 Mar 2026 956th professor-l 526 94 11ms 32 hours ago 957th kmathis22 525 91 430ms 10 days ago 958th tomh1012 523 120 136ms 2 Mar 2026 959th Schmitt-Very-Cool 521 160 290ms 5 Dec 2025 960th Stockoh 🇫🇷 519 92 435ms 9 Jan 2026 First Prev 881–960 of 1,465 Next Last