Card Number Validation in C 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 Gray Code Decoder Gray Code Encoder 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 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 Gray Code Decoder Gray Code Encoder 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 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 1st JayXon 🇺🇸 1,000 76 2ms 11 Oct 2024 1st rhdqor213 1,000 76 2ms 5 Dec 2025 3rd KasperKivimaeki 🇫🇮 962 79 2ms 6 Dec 2025 4th xsot 🇸🇬 927 82 2ms 6 May 2025 5th nwellnhof 🇩🇪 905 84 2ms 2 Oct 2024 5th ovs-code 🇩🇪 905 84 1ms 2 Nov 2024 5th inventshah 905 84 2ms 31 Mar 2025 8th saito-ta 🇯🇵 894 85 1ms 1 Oct 2024 9th MeWhenI 🇻🇦 864 88 1ms 2 Oct 2024 10th retrohun 844 90 2ms 29 hours ago 11th luuumine 🇫🇷 826 92 1ms 5 Dec 2025 11th bzd7 826 92 2ms 7 Dec 2025 13th sean-niemann 🇺🇸 817 93 1ms 24 Oct 2024 14th stefangimmillaro 809 94 1ms 30 Oct 2024 14th emgordon154 809 94 2ms 7 Feb 2026 16th Alex-x90 🇺🇸 760 100 2ms 1 Oct 2024 17th madex 🇩🇪 738 103 1ms 2 Oct 2024 17th solisolu 738 103 2ms 2 days ago 19th BlankSpruce 731 104 2ms 1 Oct 2024 20th Herbert00709 🇵🇱 724 105 2ms 14 Jun 2025 21st rniii 717 106 1ms 2 Oct 2024 21st gastropner 717 106 2ms 11 Feb 2025 23rd Yax42 🇫🇷 704 108 2ms 12 days ago 24th Jonatan6 🇩🇰 691 110 2ms 24 Oct 2024 25th not-a-pokemon 673 113 1ms 23 Jul 2025 26th jupj 🇫🇮 667 114 2ms 20 Jul 2025 27th roguh 🇬🇹 650 117 1ms 13 Oct 2024 27th iczelia 🇩🇪 650 117 2ms 25 Sep 2025 29th bac0id 639 119 2ms 10 Jan 2025 30th Mabeloid 🇳🇴 628 121 1ms 21 Oct 2025 31st jgbaldwinbrown 618 123 2ms 14 Jan 2026 32nd mousetail 🇳🇱 594 128 2ms 3 Oct 2024 33rd dokutan 580 131 2ms 10 Feb 2026 34th isaiah0311 🇺🇸 563 135 2ms 9 Feb 2026 34th jusaka 563 135 2ms 3 days ago 36th jlangvand 539 141 1ms 15 Oct 2024 36th HumanoidCPU 539 141 1ms 7 Mar 2025 38th h-hh-hhh 🇺🇦 517 147 1ms 2 Nov 2024 39th jbjd 503 151 2ms 4 Feb 2026 40th aksyristos 442 172 2ms 23 Nov 2025 41st c0d3-4-F00d 🇩🇪 413 184 2ms 9 Jan 2025 42nd sciencejiho 386 197 2ms 11 Feb 2025 43rd Inbarw100 367 207 2ms 34 hours ago 44th kasarino 317 240 2ms 8 Feb 2026 45th KatieLG 🇬🇧 315 241 2ms 1 Oct 2025 1–45 of 45
