The Calendar hole will go live in approximately 13 days. Why not try and solve it ahead of time?
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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 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 Calendar 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 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 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 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 Calendar 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 881st dokutan 654 132 2ms 13 Aug 2024 881st gonengazit 654 132 2ms 13 Apr 2025 883rd Yewzir 🇧🇪 653 139 327ms 24 Feb 2023 884th SirBogman 🇺🇸 651 96 414ms 16 Jan 2024 884th Jacob385 651 96 363ms 13 Nov 2024 886th Bulmenisaurus 651 106 10ms 2 Feb 2025 887th HumanoidCPU 651 118 338ms 3 Mar 2025 888th sjrct 651 144 2ms 4 Aug 2024 889th jhpaques 🇫🇷 651 199 42ms 13 Dec 2022 890th jared-hughes 650 40 55ms 29 Jul 2022 891st 4hg 🇺🇸 650 69 46ms 30 Nov 2022 891st Andriamanitra 🇫🇮 650 69 42ms 17 Apr 2023 893rd jkelly467 650 116 4,546ms 14 Nov 2025 894th cbrt-x 650 164 427ms 16 Jan 2022 895th KevinMarquette 🇺🇸 648 85 247ms 17 Apr 2022 895th snoozingnewt 🇨🇦 648 85 220ms 20 Nov 2023 897th xyangst 648 109 9ms 7 Oct 2024 897th snoozingnewt 🇨🇦 648 109 9ms 9 Oct 2025 899th vgamula 🇺🇦 648 195 33ms 31 Oct 2023 900th MeWhenI 🇻🇦 647 47 3ms 11 Jan 2022 901st biocommando 🇫🇮 647 145 2ms 26 Dec 2022 901st kallmi28 🇨🇿 647 145 2ms 13 Oct 2023 901st rifatx 647 145 1ms 14 Jul 2024 904th HumanoidCPU 647 186 155ms 4 Mar 2025 905th saito-ta 🇯🇵 645 102 23ms 1 Jul 2022 906th fourth-bit 645 107 9ms 10 Jul 2024 906th fuzzylojik-golf 🇺🇸 645 107 10ms 19 May 2025 906th solisolu 645 107 10ms 23 days ago 909th mckymsh 643 110 9ms 17 Feb 2024 909th madex 🇩🇪 643 110 9ms 6 Jun 2024 909th madeforlosers 643 110 9ms 13 Sep 2024 909th gigaprofisi 🇺🇸 643 110 9ms 4 Sep 2025 913th Yewzir 🇧🇪 643 120 101ms 1 Dec 2023 914th JRaspass 🇬🇧 643 170 2ms 9 Sep 2022 915th BREMAUCY 🇫🇷 642 202 41ms 14 Feb 2025 916th MeWhenI 🇻🇦 641 96 135ms 25 Oct 2024 917th emgordon154 640 126 5ms 20 Feb 2025 918th jwhear 🇺🇸 640 188 145ms 9 May 2023 919th prplz 🇦🇺 639 108 10ms 11 Jan 2022 919th galloj 🇨🇿 639 108 10ms 21 Sep 2022 919th TaserTheFox 🇺🇸 639 108 9ms 3 Apr 2023 919th cros107 🇦🇺 639 108 10ms 10 Aug 2025 923rd Chinay-Domitrix 🇺🇸 639 118 3,648ms 4 Nov 2025 924th jwhear 🇺🇸 639 230 1,707ms 30 Sep 2024 924th msbranicky 639 230 1,673ms 17 Sep 2025 926th fuzzylojik-golf 🇺🇸 638 98 406ms 6 Jul 2025 927th bwat2 638 167 378ms 13 Jan 2022 927th rifatx 638 167 414ms 23 Jul 2024 929th albanian-laundromat 638 367 11ms 13 days ago 930th m-tkach 🇺🇦 635 121 329ms 10 Jan 2022 930th arctouch-cristiannevianna 635 121 332ms 1 Mar 2024 930th acer-xq 635 121 394ms 5 Aug 2024 933rd edsrzf 🇳🇿 634 41 47ms 3 Nov 2025 934th dokutan 634 48 2ms 15 Nov 2024 935th Natanaelel 🇸🇪 634 62 32ms 21 Jun 2022 936th cefqrn 633 109 9ms 24 Dec 2022 936th AlexanderFair 633 109 10ms 11 Jul 2023 936th firegene 🇮🇪 633 109 10ms 18 Jan 2024 936th andrewjc2000 633 109 10ms 9 Mar 2025 940th MaxElf999 633 148 2ms 19 Dec 2022 941st astdefu 633 173 486ms 9 Dec 2022 942nd DialFrost 🇸🇬 632 71 42ms 26 Dec 2024 943rd MeWhenI 🇻🇦 632 200 31ms 7 Jun 2023 944th dokutan 632 205 42ms 31 Oct 2024 945th Kokusui 🇯🇵 630 132 5ms 22 Jul 2024 946th 0xjac 🇨🇭 630 210 276ms 9 Jun 2025 947th Yewzir 🇧🇪 629 135 7ms 16 Dec 2023 947th Maximizer02 629 135 8ms 24 Sep 2024 949th gastropner 629 149 2ms 8 Jul 2025 950th sultan 627 110 9ms 24 Feb 2024 950th fgrosshans 🇫🇷 627 110 10ms 16 Jul 2024 950th edsrzf 🇳🇿 627 110 9ms 30 Jul 2025 950th InigoK 🇺🇸 627 110 10ms 22 Sep 2025 950th vhoulbreque 🇫🇷 627 110 11ms 23 days ago 955th crizin 🇰🇷 627 170 389ms 10 Sep 2023 956th NicolasBn 🇫🇷 626 88 297ms 11 Jan 2022 957th MeWhenI 🇻🇦 626 93 307ms 14 Feb 2023 958th recursive-x 626 175 397ms 24 Jan 2023 958th tomh1012 626 175 1,104ms 27 days ago 960th edsrzf 🇳🇿 625 107 73ms 28 Jun 2025 First Prev 881–960 of 1,556 Next Last