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?
Emirp Numbers in Python 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 641st connernewman 372 148 10ms 27 Jun 2018 641st lukasmoellerch 372 148 12ms 14 Jan 2019 641st YoungjuneKwon 372 148 15ms 22 Feb 2019 641st ElevatorShaft 372 148 10ms 19 Jun 2019 641st sawall 372 148 10ms 17 Aug 2019 641st jaredcrystal 🇺🇸 372 148 9ms 29 Oct 2019 641st dim-an 372 148 9ms 9 Dec 2020 641st silvncr 372 148 10ms 16 Jun 2021 641st inishawl 372 148 9ms 16 Jun 2021 641st theunofficialcoder 372 148 9ms 1 Sep 2021 641st kurkale6ka 372 148 10ms 7 Sep 2021 641st bwat2 372 148 10ms 2 Nov 2021 641st tston529 372 148 28ms 24 Feb 2022 641st SpareManiKatti 372 148 10ms 19 Apr 2022 641st kevdah 372 148 9ms 10 May 2022 641st bwenstar 372 148 10ms 21 Feb 2024 641st Ch3ngL0rd 372 148 10ms 5 Mar 2024 641st Bit125 372 148 10ms 28 Mar 2024 641st RedzGoose 🇦🇺 372 148 9ms 20 Oct 2024 641st itljan30 372 148 20ms 30 Jan 2025 641st RYSF13 🇨🇳 372 148 9ms 5 Jul 2025 662nd knobz12 369 149 9ms 25 Apr 2021 662nd osmith93 369 149 9ms 31 Jul 2021 662nd aazuspan 369 149 14ms 25 Nov 2021 662nd qwjhvbxi 369 149 34ms 6 Feb 2024 662nd aaardwark 369 149 16ms 2 Jun 2025 667th willzywiec 367 150 13ms 9 Aug 2018 667th elldur 367 150 11ms 17 Mar 2019 667th hardlyBearable 367 150 10ms 20 May 2019 667th devRND-ess 367 150 12ms 29 Apr 2020 667th chrishm909 367 150 15ms 31 May 2021 667th janga1 367 150 113ms 16 Aug 2021 667th murugan-k-0204 367 150 14ms 7 Oct 2022 667th willschremmer 367 150 25ms 14 May 2024 667th VictorStenvers 🇳🇱 367 150 10ms 23 Apr 2025 667th benvreeves 367 150 10ms 25 Jul 2025 677th romglu 364 151 12ms 29 Sep 2018 677th babakoban 364 151 9ms 30 Aug 2019 677th AkshatAggarwal14 364 151 10ms 24 Jan 2022 677th willdaspit 364 151 10ms 4 Aug 2023 681st SethForrest 362 152 21ms 2 Feb 2019 681st CoffeeVector 362 152 22ms 22 Nov 2021 681st 104210 362 152 11ms 28 May 2022 681st Bananapants22 362 152 10ms 27 Aug 2022 685th patricksliwinski 359 153 12ms 21 Jul 2019 685th GameChaos 359 153 14ms 3 Sep 2020 685th voidgloom 359 153 10ms 24 Oct 2024 688th lverweijen 357 154 10ms 17 Mar 2018 688th PineappleLord 357 154 10ms 22 Aug 2018 688th Thonoton 357 154 10ms 9 Mar 2023 688th DrPrettyman 357 154 12ms 6 Jul 2023 688th lchaumartin 357 154 9ms 22 Aug 2024 688th gsprochette 357 154 11ms 22 Aug 2025 694th hanyuone 355 155 20ms 3 Dec 2017 694th Joe0400Student 355 155 17ms 2 Nov 2021 694th eddvrs 355 155 32ms 20 Aug 2022 694th cthierfelder 🇲🇨 355 155 16ms 3 Sep 2025 698th jm600 353 156 12ms 16 Apr 2022 698th tterem 353 156 9ms 8 Jun 2022 698th dylanjones92 353 156 20ms 25 Jan 2024 698th OSYCh314 🇦🇺 353 156 13ms 12 Nov 2024 698th kevinnaviapaiva 353 156 11ms 15 Feb 2025 703rd Drummerboy444 350 157 12ms 16 Jun 2019 703rd glf818 350 157 11ms 21 Jul 2021 703rd wobblybits 350 157 12ms 23 Aug 2025 706th VictorFordham 348 158 21ms 11 Aug 2020 706th HSavich 348 158 42ms 2 Dec 2021 706th bthalheim 348 158 11ms 8 Sep 2022 709th HorseScary 346 159 9ms 16 Nov 2021 710th EmadAIsmael 344 160 27ms 16 Jan 2019 710th jpyCode 344 160 22ms 24 Feb 2019 710th CodyKlingler 344 160 20ms 7 Feb 2025 713th zerickso 342 161 18ms 17 Mar 2024 713th SURAJMITTAL 342 161 11ms 19 Dec 2024 713th NoneTheFewer 342 161 12ms 25 Dec 2025 716th monishnene 340 162 99ms 1 Mar 2019 716th KiwiKoder0123 340 162 14ms 22 Jun 2019 716th ItsMeNoobieboy 340 162 24ms 23 Dec 2022 716th ComputerKWasTaken 🇺🇸 340 162 10ms 1 Jun 2024 720th biinari 337 163 17ms 19 Mar 2018 First Prev 641–720 of 813 Next Last