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 561st andersk 🇺🇸 771 156 236ms 30 Oct 2022 561st emgordon154 771 156 243ms 14 Mar 2025 563rd nwellnhof 🇩🇪 770 54 4ms 22 May 2022 564th DialFrost 🇸🇬 770 142 2ms 14 Sep 2024 565th primo-ppcg 🇹🇭 769 118 337ms 9 Apr 2022 566th scpchicken 🇵🇼 768 55 148ms 13 Mar 2022 567th maxpelic 🇺🇸 768 92 9ms 5 Jul 2022 567th astdefu 768 92 9ms 10 Dec 2022 567th two-bad 🇬🇧 768 92 9ms 25 Feb 2024 567th dokutan 768 92 9ms 15 Jun 2025 571st c0d3-4-F00d 🇩🇪 768 122 2ms 21 Feb 2022 572nd Steffan153 🇫🇮 768 132 13ms 5 Jul 2024 573rd Shanethegamer 🇺🇸 766 76 449ms 12 Oct 2022 574th sjrct 766 90 10ms 5 Aug 2024 574th webmiche 766 90 10ms 3 Nov 2025 576th Shanethegamer 🇺🇸 766 157 149ms 8 Oct 2022 577th ovs-code 🇩🇪 765 34 51ms 14 May 2024 578th juliansiebert 🇩🇪 765 72 274ms 24 Jul 2022 579th stefangimmillaro 765 76 998ms 8 Jan 2023 579th MeWhenI 🇻🇦 765 76 997ms 10 May 2023 579th error256 765 76 1,078ms 14 Feb 2025 582nd emplv 🇱🇻 763 101 100ms 6 Dec 2022 583rd Yewzir 🇧🇪 763 115 139ms 26 Dec 2023 584th iczelia 🇩🇪 762 123 1ms 24 Sep 2025 585th rak1507 🇬🇧 761 40 2ms 10 Jan 2022 585th Frowny 761 40 2ms 13 Jan 2022 585th razetime 761 40 3ms 22 Aug 2022 588th jerrandolph 761 174 251ms 20 Oct 2023 589th MeWhenI 🇻🇦 760 43 4ms 1 Mar 2025 590th MeWhenI 🇻🇦 760 59 48ms 24 Aug 2022 590th janlelis 760 59 56ms 21 Sep 2024 592nd Andrey-Plotnikov 760 93 9ms 21 Jun 2025 592nd Protothor 760 93 9ms 9 Jul 2025 594th kejcao 🇨🇦 760 147 193ms 3 Aug 2024 595th dokutan 759 81 118ms 15 Jun 2025 596th DialFrost 🇸🇬 759 133 6ms 11 Dec 2024 597th P-Quentin 🇫🇷 758 91 10ms 5 Aug 2022 597th Rubiksmath 758 91 16ms 28 Jun 2024 597th wh3n3v3r 🇨🇿 758 91 10ms 11 Nov 2024 600th GrayJoKing 🇦🇺 758 126 421ms 1 Mar 2022 601st primo-ppcg 🇹🇭 757 67 20ms 24 Jan 2022 602nd DialFrost 🇸🇬 757 114 2ms 1 Nov 2024 603rd annaproxy 757 134 13ms 24 Dec 2022 604th MeWhenI 🇻🇦 757 194 1,694ms 7 Nov 2025 605th xsot 🇸🇬 756 55 3ms 6 Jul 2025 606th stefangimmillaro 756 102 99ms 19 Oct 2022 607th djeedjay 🇳🇱 756 124 2ms 16 Sep 2022 608th MeWhenI 🇻🇦 755 81 699ms 15 Sep 2025 609th Shanethegamer 🇺🇸 754 73 264ms 14 Jun 2024 610th HumanoidCPU 753 83 356ms 2 Mar 2025 611th ovs-code 🇩🇪 753 87 4ms 8 Mar 2023 612th MeWhenI 🇻🇦 753 128 8ms 21 Jul 2023 613th Starwort 🇬🇧 750 92 10ms 17 Mar 2023 613th cingulataluke 750 92 10ms 29 Aug 2023 615th Ripick 750 121 329ms 11 Jul 2024 616th jupj 🇫🇮 750 125 2ms 31 Aug 2022 617th albanian-laundromat 750 133 42ms 7 Sep 2025 618th MeWhenI 🇻🇦 750 146 68ms 13 Nov 2022 618th janbehrens 🇩🇪 750 146 66ms 23 Jun 2023 620th edsrzf 🇳🇿 749 97 68ms 7 Oct 2025 621st edsrzf 🇳🇿 749 173 41ms 28 Jun 2025 622nd Steffan153 🇫🇮 748 135 6ms 12 Mar 2023 623rd Shanethegamer 🇺🇸 748 251 1,538ms 25 Jan 2025 624th anter69 🇭🇺 747 60 44ms 12 Feb 2024 625th edsrzf 🇳🇿 747 78 448ms 11 Oct 2025 626th nwellnhof 🇩🇪 747 88 31ms 12 Jul 2022 627th elgan65536 747 161 145ms 9 Nov 2023 628th emgordon154 746 128 577ms 3 Jun 2025 629th tobeannouncd 745 150 144ms 20 Dec 2024 630th dylanarmstrong 744 95 9ms 12 Jan 2024 630th junkondo-jp 744 95 9ms 2 Jun 2024 632nd chlorobenzene12 744 116 2ms 26 Dec 2022 633rd KrausRaus 🇺🇸 744 117 2ms 15 Oct 2023 634th bac0id 744 126 2ms 3 Jul 2024 635th edsrzf 🇳🇿 744 134 41ms 28 Jun 2025 636th stackofbears 742 41 2ms 20 Feb 2022 636th akamayu-ouo 🇹🇼 742 41 2ms 8 Jul 2024 636th AlephSquirrel 742 41 3ms 8 Nov 2025 639th Frowny 742 53 32ms 11 Jan 2022 640th QuincyNash 🇺🇸 742 93 17ms 21 Jan 2022 First Prev 561–640 of 1,556 Next Last