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Collatz in C 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 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 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 Apéry’s Constant Binary Lambda Calculus Connect Four Continued Fractions Crossword CSS Colors (Inverse) CSS Grid Ellipse Perimeters Flags Floyd-Steinberg Dithering Gray Code Decoder Gray Code Encoder Hexagonal Spiral Highly Composite Numbers Multitap Input NFA Simulator Numbrix Odd Polyomino Tiling p-adic Expansion Polygon Triangulations QR Encoder Quadratic Formula Semiprime Numbers Smooth Numbers Snake Sphenic Numbers Taxicab Numbers Turtle Tutorial All Languages ><> 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 ALGOL 68 APL ArkScript Arturo Befunge BQN CJam CoffeeScript Egel Fennel Harbour Hare Haxe Hush Hy iogii Knight Luau Odin Picat Qore Racket Rebol Rexx Scala Squirrel Stax Uiua Umka Vala Vyxal Bytes Chars Scoring Bytes Chars Language All ><> 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 ALGOL 68 APL ArkScript Arturo Befunge BQN CJam CoffeeScript Egel Fennel Harbour Hare Haxe Hush Hy iogii Knight 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 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 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 Apéry’s Constant Binary Lambda Calculus Connect Four Continued Fractions Crossword CSS Colors (Inverse) CSS Grid Ellipse Perimeters Flags Floyd-Steinberg Dithering Gray Code Decoder Gray Code Encoder Hexagonal Spiral Highly Composite Numbers Multitap Input NFA Simulator Numbrix Odd Polyomino Tiling p-adic Expansion Polygon Triangulations QR Encoder Quadratic Formula Semiprime Numbers Smooth Numbers Snake Sphenic Numbers Taxicab Numbers Turtle Tutorial # Golfer Points Chars Time Submitted 159th piano-miles 744 86 2ms 30 Mar 2023 162nd razetime 736 87 2ms 22 Aug 2022 163rd james-downey 727 88 2ms 9 Jul 2022 163rd jhpaques 🇫🇷 727 88 2ms 4 Dec 2022 163rd mamalakic 727 88 2ms 1 Mar 2023 163rd xnacly 🇩🇪 727 88 2ms 5 Jul 2023 163rd KrausRaus 🇺🇸 727 88 2ms 31 Jul 2023 163rd dranjohn 727 88 3ms 17 Sep 2023 163rd roguh 🇬🇹 727 88 2ms 15 Jan 2024 163rd northsuperman 727 88 2ms 24 Mar 2024 171st RealAMC 🇳🇿 719 89 2ms 15 Nov 2023 171st mathb0y512 719 89 2ms 25 Jun 2024 171st Mabeloid 🇳🇴 719 89 2ms 25 Sep 2024 174th Starwort 🇬🇧 711 90 2ms 11 Nov 2022 175th astdefu 703 91 2ms 10 Dec 2022 175th msbranicky 703 91 2ms 9 Jan 2024 177th esseeffeenne 696 92 2ms 6 Jun 2022 177th MaxElf999 696 92 2ms 5 Feb 2023 177th ComputerKWasTaken 🇺🇸 696 92 2ms 20 Jan 2025 177th matejmatik123 🇸🇰 696 92 2ms 6 Jul 2025 181st LawrenceZ1A 🇨🇦 688 93 3ms 25 May 2022 181st jaxmattfair 🇺🇸 688 93 2ms 10 Jan 2023 181st Maximizer02 688 93 2ms 7 May 2024 181st 0dyse 688 93 2ms 23 Apr 2025 185th Smetalo 681 94 2ms 25 Aug 2022 185th evan18c 681 94 6ms 12 Dec 2023 187th Andrey2001 674 95 2ms 27 Nov 2025 188th kmathis22 667 96 2ms 25 Sep 2025 189th NeatCrown 🇨🇦 660 97 2ms 14 Dec 2022 190th calinous 🇷🇴 653 98 2ms 2 Mar 2023 190th jtaxen 653 98 2ms 14 Apr 2024 192nd 6512345 646 99 2ms 8 Nov 2025 193rd Azearia 640 100 2ms 6 Jul 2023 194th Sephirem98 627 102 2ms 25 Oct 2023 194th ottav14 627 102 2ms 1 Dec 2025 196th galloj 🇨🇿 621 103 2ms 20 May 2023 196th Pyro569 621 103 2ms 28 Jul 2023 198th TornadoCookie 604 106 2ms 17 Oct 2022 199th aarooosh 598 107 2ms 8 Aug 2024 200th dillon-duncando 593 108 2ms 22 Sep 2022 200th blaztoma 🇱🇹 593 108 3ms 18 Nov 2025 202nd masflam 587 109 2ms 21 Jun 2024 203rd tweska 🇳🇱 582 110 2ms 5 Jun 2023 203rd Jaro32768 🇸🇰 582 110 2ms 8 Feb 2024 203rd 0xA00 582 110 2ms 3 Dec 2025 206th michztl01 577 111 2ms 1 Jun 2022 207th kenballus 571 112 2ms 13 Jul 2022 207th nandanjp 571 112 2ms 29 Mar 2023 207th CyberTapir 571 112 2ms 27 Aug 2024 210th Giantnoodlemonster 566 113 2ms 14 Sep 2024 211th pinguicula 561 114 2ms 6 Apr 2023 211th fkantelberg 561 114 2ms 15 Jul 2023 211th Blockyheadman 561 114 2ms 6 Nov 2025 214th TerenceTux 557 115 2ms 22 May 2023 215th tik25 547 117 2ms 28 Mar 2024 216th 104210 533 120 2ms 29 Jul 2022 217th Qruintrox 529 121 2ms 25 Jun 2023 218th aDwarfNamedUrist 525 122 2ms 12 Jul 2023 218th Alex-Huggett 🇬🇧 525 122 2ms 14 Apr 2024 220th cgjohannsen 520 123 2ms 12 Jun 2022 221st TotoAJ 512 125 2ms 15 Dec 2023 221st mrmena 🇦🇺 512 125 2ms 19 Mar 2024 223rd StronkCheese 🇺🇸 508 126 2ms 18 Feb 2023 224th MEarley 496 129 2ms 19 Sep 2023 225th wearsunscreen 481 133 2ms 19 Oct 2023 226th 4ndyJ 🇬🇧 478 134 2ms 16 Dec 2022 226th programmeruser2 478 134 2ms 3 Mar 2023 228th AstroOrbis 464 138 3ms 10 Jul 2025 229th julianreece 460 139 2ms 29 Apr 2025 230th myclevorname 🇺🇸 441 145 2ms 20 Aug 2023 231st Bodo171 438 146 2ms 6 Dec 2022 232nd jameswmccarty 432 148 2ms 24 Sep 2024 233rd craftablescience 410 156 2ms 19 Sep 2023 234th NOS4A5I 405 158 2ms 30 Dec 2022 235th calum12345 390 164 3ms 27 Mar 2025 236th george1605 337 190 3ms 14 Feb 2023 237th kevinnaviapaiva 317 202 3ms 20 Feb 2025 238th taha-daneshmand 186 344 3ms 2 Oct 2024 239th MaNafromSaar 167 384 2ms 14 Nov 2023 240th somT-oss 148 432 2ms 26 Nov 2024 First Prev 161–240 of 243 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