The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 4 days. Why not try and solve them ahead of time?
Zeckendorf Representation 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 561st commandz0 🇺🇸 654 136 541ms 1 Sep 2025 562nd snoozingnewt 🇨🇦 654 177 108ms 8 Oct 2025 563rd OCNeve 652 164 10ms 3 Jul 2024 563rd muser-logiccpu 🇺🇦 652 164 10ms 9 Aug 2025 565th AtengChen 648 165 11ms 14 Aug 2024 566th kmathis22 648 173 566ms 22 Oct 2025 567th dokutan 645 153 2ms 2 Jul 2024 568th CaedenHarper 🇨🇦 642 159 408ms 17 Oct 2025 569th Feniske 🇫🇷 641 106 284ms 20 Jul 2024 570th jatloe 637 168 11ms 24 Aug 2024 570th SB-945 637 168 11ms 10 Jan 2025 572nd MeWhenI 🇻🇦 636 111 5ms 1 Jul 2024 573rd msbranicky 632 156 2ms 5 Jul 2024 574th CatsAreFluffy 630 100 49ms 15 Nov 2024 575th MeWhenI 🇻🇦 630 137 110ms 1 Jul 2024 576th msbranicky 630 184 98ms 5 Jul 2024 577th mousetail 🇳🇱 629 137 2ms 1 Jul 2024 578th msbranicky 629 163 2,703ms 7 Jan 2025 579th marcin7Cd 629 170 9ms 11 Jul 2024 579th YAJUE114514 629 170 11ms 31 Jul 2025 581st msbranicky 629 216 277ms 4 Jul 2024 582nd SirBogman 🇺🇸 628 200 44ms 3 Jun 2025 583rd MeWhenI 🇻🇦 627 160 4ms 2 Jul 2024 584th sheen4n 626 171 11ms 21 Jul 2024 584th dokutan 626 171 10ms 11 Jan 2026 586th bac0id 622 176 461ms 1 Jul 2024 587th msbranicky 622 185 363ms 5 Jul 2024 588th HumanoidCPU 618 144 474ms 31 Oct 2024 589th klixel 🇨🇦 618 173 13ms 20 Jan 2025 590th croc54 615 174 9ms 17 Jan 2025 591st emgordon154 607 108 34ms 26 Jul 2024 592nd Shanethegamer 🇺🇸 604 92 113ms 24 Sep 2024 593rd olleicua 🇺🇸 602 109 36ms 3 Jul 2024 594th LukeBridges 🇬🇧 602 115 12ms 10 Oct 2024 595th coldham10 601 178 11ms 13 Jan 2026 596th MarcMush 🇫🇷 597 118 379ms 31 Jul 2024 597th jared-hughes 596 113 21ms 4 Jul 2024 598th madex 🇩🇪 594 180 10ms 1 Jul 2024 599th junkondo-jp 592 117 13ms 15 Dec 2024 600th edsrzf 🇳🇿 589 181 10ms 24 Nov 2024 601st Andrey2001 585 152 554ms 28 Jan 2026 602nd emgordon154 583 183 8ms 13 Dec 2024 603rd MeWhenI 🇻🇦 583 193 123ms 1 Jul 2024 604th robin-scragg 578 185 11ms 5 Jul 2025 605th Program-Pi 577 120 14ms 26 Feb 2026 606th ginop 575 186 9ms 2 Jul 2024 606th inverseLorentz 🇦🇺 575 186 11ms 8 Jul 2024 608th alemelis 573 123 712ms 26 Aug 2024 609th dokutan 568 122 11ms 5 Jun 2025 610th dokutan 568 136 151ms 5 Aug 2024 611th OllieBoyne 🇬🇧 566 189 11ms 12 Jul 2024 612th msbranicky 566 235 175ms 4 Jul 2024 613th dokutan 563 158 606ms 11 Jan 2026 614th msbranicky 563 165 211ms 4 Jul 2024 615th bac0id 561 182 394ms 1 Jul 2024 616th MeWhenI 🇻🇦 560 91 2ms 1 Jul 2024 617th tomh1012 560 191 10ms 21 Jan 2026 618th alexsave 559 124 11ms 13 Nov 2024 619th bac0id 556 155 2ms 3 Jul 2024 620th Mabeloid 🇳🇴 554 193 11ms 11 Sep 2024 621st MeWhenI 🇻🇦 548 179 68ms 9 Aug 2024 622nd weliveinhell 🇭🇹 546 127 11ms 4 Jul 2024 623rd MeWhenI 🇻🇦 546 199 1,363ms 2 Jul 2024 624th JOrE20 544 125 326ms 24 Dec 2025 625th dokutan 542 121 36ms 28 Sep 2024 626th zakariamouhid 537 129 13ms 3 Jul 2024 627th snoozingnewt 🇨🇦 533 130 11ms 29 Sep 2025 628th zt14427 527 203 9ms 1 Jul 2024 629th Salutations45 525 97 2ms 29 Dec 2024 630th luuumine 🇫🇷 519 166 2ms 1 Dec 2025 631st dokutan 517 180 214ms 1 Jul 2024 632nd madex 🇩🇪 516 127 36ms 1 Jul 2024 633rd klixel 🇨🇦 513 259 243ms 9 Jan 2025 634th MeWhenI 🇻🇦 511 198 47ms 6 Aug 2024 635th msbranicky 511 265 57ms 4 Jul 2024 636th KatieLG 🇬🇧 509 136 11ms 1 Jul 2024 637th Maximizer02 508 210 12ms 24 Jul 2024 638th 0xjac 🇨🇭 505 269 285ms 19 Jun 2025 639th ComputerKWasTaken 🇺🇸 504 130 35ms 4 Jul 2024 640th bac0id 498 225 465ms 1 Jul 2024 First Prev 561–640 of 733 Next Last