The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 31 hours. Why not try and solve them ahead of time?
Collatz in Python 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 720th NOS4A5I 630 100 18ms 10 Jan 2023 720th lomarbrick 630 100 18ms 16 May 2023 720th karlaacastro44 630 100 18ms 5 May 2025 724th markus-rekdal 624 101 23ms 10 May 2022 724th fraserli 🇦🇺 624 101 23ms 2 May 2023 724th FCORMERAIS 624 101 19ms 6 Mar 2024 724th yhm138 624 101 14ms 16 Feb 2025 724th MinecraftFan69420 624 101 21ms 31 Oct 2025 729th PogLop 🇨🇿 618 102 20ms 31 Oct 2022 729th AndersH3 🇸🇪 618 102 16ms 17 May 2023 729th JulieGermainUNT 618 102 19ms 2 Apr 2025 729th NicoBliss 618 102 23ms 16 Nov 2025 733rd enbyte 612 103 19ms 20 Dec 2022 733rd rajlath 612 103 19ms 7 Jan 2023 733rd mnurzia 612 103 16ms 12 Oct 2023 733rd sqrteipi 612 103 20ms 2 Apr 2024 733rd calum12345 612 103 19ms 26 Mar 2025 738th winigo3 606 104 24ms 8 Aug 2022 738th zt14427 606 104 19ms 30 Apr 2023 738th IoLimmer 606 104 17ms 24 Jul 2024 738th Deneb999 606 104 24ms 26 Feb 2026 742nd LordSir101 600 105 16ms 19 Jul 2022 742nd tmanternach 600 105 19ms 24 Nov 2022 742nd weber-hge 600 105 15ms 13 Jun 2023 742nd Eugen-str 600 105 20ms 24 Oct 2023 746th ms-tingliang 594 106 15ms 5 Aug 2022 746th achilleasr 594 106 20ms 7 Nov 2022 746th OleBrumm 594 106 21ms 8 Jan 2023 746th AbhilashaTandon 594 106 20ms 19 Sep 2023 746th sheeperino 🇮🇹 594 106 20ms 11 Oct 2024 751st phpboyscout 589 107 17ms 18 May 2023 751st DrPrettyman 589 107 15ms 5 Jul 2023 751st joseph-w0ng 589 107 15ms 5 Jul 2024 751st EnisEfe0 589 107 20ms 18 May 2025 755th landyrisbad 583 108 19ms 13 Nov 2022 755th cakular 583 108 25ms 17 May 2024 755th glassala 583 108 15ms 25 Oct 2024 755th CarterStroik 583 108 19ms 12 Nov 2025 759th tjefferson401 578 109 29ms 16 Sep 2022 759th ariesmarinus 578 109 16ms 21 Nov 2024 761st profJGermain 573 110 20ms 7 Feb 2024 761st JMMMMC 573 110 20ms 23 Oct 2024 761st jtb0362 573 110 20ms 10 May 2025 764th sagnik3 563 112 19ms 8 Aug 2022 764th craftablescience 563 112 17ms 19 Sep 2023 766th kelseychristensen 558 113 20ms 2 Nov 2022 766th ArmsTheLimited 558 113 15ms 1 Jun 2023 768th jstechman 548 115 19ms 24 Feb 2024 768th dan422442 548 115 19ms 19 Oct 2024 770th keelanfh 543 116 16ms 20 Dec 2023 770th returnitynet 543 116 18ms 27 Jan 2025 770th EthanPatel01000101 543 116 17ms 20 Oct 2025 773rd gioto64 538 117 17ms 8 Dec 2022 773rd WilfredSalmon 538 117 18ms 21 Oct 2023 775th XianchengZ 534 118 20ms 18 Aug 2023 775th brindak2005 534 118 17ms 2 May 2025 777th jmmographer 516 122 20ms 21 Oct 2023 777th RucatJ 516 122 19ms 8 Aug 2025 779th xbxbxb007 512 123 21ms 10 Jan 2024 780th kevinnaviapaiva 488 129 18ms 20 Feb 2025 781st AdrianN001 485 130 17ms 6 Aug 2023 782nd wyatt-the-hump 481 131 16ms 24 Dec 2022 782nd hotmanga 481 131 13ms 20 Oct 2023 782nd Jordynar02 481 131 21ms 3 May 2025 785th Zach10za 474 133 23ms 23 Jan 2024 786th vtilde 470 134 17ms 8 Jan 2024 787th fig-apple 467 135 11ms 24 Jun 2023 788th S-Ruban 460 137 13ms 25 Feb 2023 789th FLOKI0421 453 139 17ms 4 May 2025 789th noahdorsch 453 139 20ms 5 May 2025 791st bartsowka2000 423 149 20ms 10 Jul 2023 792nd KapelMeister 420 150 14ms 5 Sep 2025 793rd Shegofa-Ahmadi 409 154 15ms 28 Apr 2025 794th arinhyther 406 155 17ms 24 Dec 2022 795th SebbeCaliban 401 157 18ms 11 Apr 2023 796th codefeld 364 173 20ms 5 Mar 2023 797th fl3ur1nestimable 354 178 16ms 24 Oct 2022 798th Laellekoenig 339 186 16ms 7 Nov 2025 799th Siyasia 333 189 17ms 22 Apr 2025 800th kalehika1234 326 193 14ms 24 Apr 2025 First Prev 721–800 of 842 Next Last
