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 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 CaedenHarper 🇨🇦 600 88 90ms 30 Nov 2025 882nd bitsandbeyond 🇳🇱 600 99 3ms 3 Jan 2026 883rd Natanaelel 🇸🇪 600 139 288ms 25 Dec 2025 884th Nicronmil 599 74 11ms 11 Dec 2025 884th two-bad 🇬🇧 599 74 10ms 17 Dec 2025 886th olleicua 🇺🇸 598 75 34ms 7 Dec 2025 887th JOrE20 597 81 727ms 30 Jan 2026 888th anter69 🇭🇺 597 105 84ms 26 days ago 889th CaedenHarper 🇨🇦 596 81 296ms 30 Nov 2025 890th RDShah 596 83 11ms 1 Dec 2025 891st KatieLG 🇬🇧 596 108 10ms 30 Nov 2025 892nd HumanoidCPU 594 105 378ms 29 Nov 2025 893rd Natanaelel 🇸🇪 592 106 122ms 26 days ago 894th BREMAUCY 🇫🇷 592 141 290ms 2 Dec 2025 894th JOrE20 592 141 298ms 30 Jan 2026 896th HumanoidCPU 589 74 145ms 29 Nov 2025 897th anter69 🇭🇺 589 77 1,267ms 5 Dec 2025 898th Yewzir 🇧🇪 589 82 338ms 30 Nov 2025 899th ZakkkkAttackkkk 🇵🇭 589 84 17ms 2 Feb 2026 900th FortuiteMan 🇫🇷 589 114 11ms 24 Dec 2025 901st kmathis22 589 120 406ms 22 days ago 902nd aksyristos 588 83 1ms 3 Dec 2025 903rd SwordF-Official 🇺🇸 588 92 2ms 16 Nov 2025 903rd HumanoidCPU 588 92 2ms 29 Nov 2025 903rd tomh1012 588 92 2ms 26 days ago 903rd prestosilver 🇺🇸 588 92 2ms 26 days ago 903rd BREMAUCY 🇫🇷 588 92 2ms 26 days ago 903rd m-tkach 🇺🇦 588 92 2ms 25 days ago 909th tomh1012 587 142 283ms 12 Feb 2026 910th Protothor 584 76 10ms 4 Dec 2025 910th Andrey-Plotnikov 584 76 10ms 9 Jan 2026 912th dokutan 583 73 200ms 28 Nov 2025 913th aksyristos 582 93 2ms 24 days ago 914th MeWhenI 🇻🇦 580 111 17ms 28 Nov 2025 915th emgordon154 578 56 4ms 10 days ago 916th Maashau 578 106 2ms 1 Dec 2025 917th kmathis22 576 84 780ms 7 days ago 918th BREMAUCY 🇫🇷 575 78 34ms 1 Dec 2025 919th Schmitt-Very-Cool 575 86 11ms 5 Dec 2025 920th kmathis22 575 145 278ms 8 days ago 921st HumanoidCPU 575 181 1,852ms 30 Nov 2025 922nd BREMAUCY 🇫🇷 573 109 469ms 1 Dec 2025 923rd Schmitt-Very-Cool 573 128 69ms 6 Dec 2025 924th HumanoidCPU 565 111 108ms 30 Nov 2025 925th MeWhenI 🇻🇦 564 74 104ms 24 Nov 2025 926th msbranicky 563 96 2ms 25 days ago 926th Jonson26 563 96 2ms 23 days ago 928th jameswmccarty 561 79 13ms 8 Feb 2026 929th CaedenHarper 🇨🇦 555 121 12ms 30 Nov 2025 930th bitsandbeyond 🇳🇱 553 107 4ms 16 Nov 2025 931st IISResetMe 551 90 5ms 26 days ago 932nd AstroOrbis 550 122 10ms 10 days ago 933rd SirBogman 🇺🇸 549 59 3ms 2 Dec 2025 934th HumanoidCPU 549 88 323ms 30 Nov 2025 935th dokutan 548 134 692ms 10 Dec 2025 936th matejmatik123 🇸🇰 547 142 1,403ms 16 Jan 2026 937th Yewzir 🇧🇪 545 91 5ms 26 days ago 938th kmathis22 544 91 11ms 8 days ago 939th Schmitt-Very-Cool 544 130 463ms 1 Dec 2025 940th emgordon154 541 79 3ms 24 Nov 2025 941st albanian-laundromat 541 104 1,265ms 30 Oct 2025 942nd Stockoh 🇫🇷 538 92 11ms 9 Jan 2026 943rd scpchicken 🇵🇼 537 125 10ms 1 Jan 2026 944th Matter1024 🇮🇳 536 101 2ms 26 days ago 945th AstroOrbis 536 117 94ms 26 days ago 946th lacrosse 534 84 40ms 29 Nov 2025 947th Schmitt-Very-Cool 534 142 26ms 5 Dec 2025 948th CLOStrophobic 🇮🇹 532 93 10ms 3 Dec 2025 949th scpchicken 🇵🇼 531 61 2ms 16 days ago 950th HumanoidCPU 529 95 117ms 29 Nov 2025 951st aksyristos 528 85 36ms 3 Dec 2025 952nd tomh1012 527 94 5ms 26 days ago 953rd kmathis22 525 91 430ms 7 days ago 954th tomh1012 523 120 136ms 26 days ago 955th Schmitt-Very-Cool 521 160 290ms 5 Dec 2025 956th Stockoh 🇫🇷 519 92 435ms 9 Jan 2026 957th aksyristos 519 146 27ms 3 Dec 2025 958th dokutan 517 115 2ms 26 Dec 2025 959th JRaspass 🇬🇧 516 96 5ms 26 days ago 960th logalex8369 🇺🇸 515 96 10ms 18 Dec 2025 First Prev 881–960 of 1,463 Next Last