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Collatz in Java 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 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 Bytes Time Submitted 1st JayXon 🇺🇸 1,000 88 497ms 24 Sep 2025 1st Lydxn 🇨🇦 1,000 88 409ms 12 Dec 2025 3rd DialFrost 🇸🇬 989 89 591ms 24 Sep 2025 3rd ovs-code 🇩🇪 989 89 493ms 24 Sep 2025 3rd dokutan 989 89 372ms 24 Sep 2025 3rd sean-niemann 🇺🇸 989 89 397ms 24 Sep 2025 3rd Shanethegamer 🇺🇸 989 89 477ms 25 Sep 2025 3rd nwellnhof 🇩🇪 989 89 464ms 25 Sep 2025 3rd m-tkach 🇺🇦 989 89 386ms 25 Sep 2025 3rd namelessiw 989 89 390ms 2 Oct 2025 3rd Yewzir 🇧🇪 989 89 349ms 2 Oct 2025 3rd Yax42 🇫🇷 989 89 496ms 4 Oct 2025 3rd stefangimmillaro 989 89 518ms 6 Oct 2025 3rd CaedenHarper 🇨🇦 989 89 467ms 9 Oct 2025 3rd Jacob385 989 89 515ms 27 Oct 2025 3rd MeWhenI 🇻🇦 989 89 449ms 7 Nov 2025 3rd ethanlally 989 89 380ms 10 Nov 2025 3rd snoozingnewt 🇨🇦 989 89 384ms 23 Nov 2025 3rd ScottHamper 989 89 467ms 30 Nov 2025 3rd KasperKivimaeki 🇫🇮 989 89 449ms 30 Nov 2025 21st h3ra993huskp 🇯🇵 978 90 425ms 30 Nov 2025 22nd kmathis22 967 91 370ms 20 Nov 2025 23rd albanian-laundromat 936 94 486ms 24 Sep 2025 23rd jkelly467 936 94 401ms 23 Oct 2025 23rd HumanoidCPU 936 94 497ms 8 Nov 2025 26th 123mjb 917 96 366ms 20 Nov 2025 26th noescareno 917 96 366ms 21 Nov 2025 28th Liibe 907 97 477ms 25 Sep 2025 29th Schmitt-Very-Cool 898 98 434ms 26 Sep 2025 30th beardotpdf 889 99 422ms 12 Dec 2025 31st CarterStroik 880 100 562ms 13 Nov 2025 32nd ravnskjaer 🇩🇰 838 105 494ms 15 Dec 2025 33rd tigerdan2 🇩🇪 822 107 424ms 30 Nov 2025 34th TheZwierzLF 🇵🇱 815 108 477ms 13 Dec 2025 35th Irratix 🇳🇱 698 126 430ms 4 May 2022 35th janbehrens 🇩🇪 698 126 410ms 4 May 2022 35th shellbertt 🇨🇦 698 126 408ms 4 May 2022 35th inventshah 698 126 414ms 4 May 2022 35th 5quiwyrm 698 126 404ms 4 Sep 2022 35th KrausRaus 🇺🇸 698 126 432ms 9 Sep 2022 35th Betuaredead 698 126 388ms 5 Jan 2023 35th annaproxy 698 126 377ms 7 Jan 2023 35th eMGeeneer 698 126 384ms 15 Jun 2024 35th mrondon8 698 126 400ms 2 Dec 2024 35th plastic-bottle 698 126 513ms 27 Aug 2025 46th Luca2812 693 127 397ms 12 Dec 2022 46th Apataras 693 127 386ms 16 Jul 2025 48th cbrt-x 682 129 408ms 6 May 2022 48th piano-miles 682 129 488ms 8 Feb 2023 48th lukashert 682 129 405ms 7 Jun 2023 48th bac0id 682 129 406ms 29 Jun 2024 48th yoshykai 682 129 430ms 27 Mar 2025 53rd bwat2 677 130 380ms 5 May 2022 53rd FlorianCassayre 🇫🇷 677 130 389ms 20 Sep 2022 53rd Widgitty 677 130 396ms 29 May 2023 56th SiestaGuru 672 131 390ms 9 Jan 2023 57th c0d3-4-F00d 🇩🇪 667 132 402ms 6 May 2022 57th madeforlosers 667 132 415ms 26 Oct 2023 57th Blockyheadman 667 132 409ms 1 Nov 2023 57th SpiritAxolotl 🇺🇸 667 132 383ms 20 Mar 2024 61st althryenix 657 134 398ms 25 Jul 2022 61st MrGagnonHPS 657 134 401ms 1 Nov 2023 63rd lukehewittvandy 652 135 388ms 18 Jul 2022 63rd OriEy 652 135 418ms 27 Apr 2023 63rd Maximizer02 652 135 402ms 8 Jun 2024 63rd 0dyse 652 135 421ms 23 Apr 2025 67th crizin 🇰🇷 647 136 397ms 9 Sep 2023 68th eshilo-draper 642 137 395ms 4 Sep 2022 69th azka1368 638 138 396ms 23 Nov 2023 70th Smetalo 633 139 388ms 25 Aug 2022 70th ToxicP1e 633 139 416ms 2 Mar 2023 72nd yashima 624 141 419ms 19 Oct 2024 72nd matas132 624 141 399ms 16 Sep 2025 72nd katss2 624 141 425ms 19 Sep 2025 75th msbranicky 607 145 407ms 9 Jan 2024 76th deancureton 603 146 369ms 24 Mar 2024 77th pyuraii 591 149 397ms 27 Sep 2022 77th Chinay-Domitrix 🇺🇸 591 149 408ms 29 Mar 2025 79th KyleLashmet 587 150 408ms 18 Jul 2022 79th Pyro569 587 150 418ms 20 Jul 2023 1–80 of 109 Next Last