The Calendar hole will go live in approximately 8 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 Bytes Time Submitted 639th mossprescott 781 113 9ms 16 Jan 2023 639th SB-945 781 113 10ms 19 Aug 2023 639th davitf 781 113 9ms 30 Apr 2024 639th kbeat 🇰🇿 781 113 12ms 18 May 2025 645th AlephSquirrel 781 130 6ms 21 Oct 2024 646th LHLaurini 🇧🇷 781 141 59ms 17 Jul 2024 647th adamnielson42 🇺🇸 780 91 9ms 26 Apr 2023 647th luuumine 🇫🇷 780 91 9ms 12 Nov 2025 649th Shanethegamer 🇺🇸 780 104 72ms 4 Dec 2024 650th Shanethegamer 🇺🇸 780 161 41ms 13 Feb 2025 651st MeWhenI 🇻🇦 779 43 4ms 1 Mar 2025 652nd MeWhenI 🇻🇦 779 96 135ms 25 Oct 2024 653rd fuzzylojik-golf 🇺🇸 779 98 406ms 6 Jul 2025 654th retrohun 778 121 2ms 30 Dec 2022 654th abc7-12 778 121 1ms 26 Jun 2024 656th Yewzir 🇧🇪 778 135 7ms 16 Dec 2023 656th Maximizer02 778 135 8ms 24 Sep 2024 658th JRaspass 🇬🇧 776 60 3ms 18 Jan 2023 659th call23re 776 112 2ms 12 Jan 2022 660th kmathis22 776 138 444ms 30 Oct 2025 661st rak1507 🇬🇧 775 40 2ms 10 Jan 2022 661st Frowny 775 40 2ms 13 Jan 2022 661st jared-hughes 775 40 55ms 29 Jul 2022 661st razetime 775 40 3ms 22 Aug 2022 665th Shanethegamer 🇺🇸 775 76 449ms 12 Oct 2022 665th stefangimmillaro 775 76 998ms 8 Jan 2023 665th MeWhenI 🇻🇦 775 76 997ms 10 May 2023 665th error256 775 76 1,078ms 14 Feb 2025 669th primo-ppcg 🇹🇭 775 118 337ms 9 Apr 2022 670th primo-ppcg 🇹🇭 775 131 6ms 20 Jan 2023 671st Steffan153 🇫🇮 775 132 13ms 5 Jul 2024 672nd DialFrost 🇸🇬 775 142 2ms 14 Sep 2024 673rd strout 775 145 148ms 15 Aug 2022 674th andersk 🇺🇸 775 156 236ms 30 Oct 2022 674th emgordon154 775 156 243ms 14 Mar 2025 676th aonkeeper4 774 114 9ms 5 Jul 2022 676th frankgraziano 774 114 10ms 8 Jan 2023 676th m42km 774 114 9ms 22 Nov 2023 676th thienudomsrirungruang 774 114 16ms 14 May 2024 676th jtaxen 774 114 10ms 8 Jun 2024 676th CutSandstone 774 114 9ms 8 Jul 2024 682nd juliansiebert 🇩🇪 773 72 274ms 24 Jul 2022 683rd maxpelic 🇺🇸 772 92 9ms 5 Jul 2022 683rd astdefu 772 92 9ms 10 Dec 2022 683rd two-bad 🇬🇧 772 92 9ms 25 Feb 2024 683rd KatieLG 🇬🇧 772 92 9ms 8 Jul 2024 687th Steffan153 🇫🇮 772 106 79ms 21 Jun 2024 688th c0d3-4-F00d 🇩🇪 772 122 2ms 21 Feb 2022 689th emplv 🇱🇻 771 101 100ms 6 Dec 2022 690th Yewzir 🇧🇪 770 115 139ms 26 Dec 2023 691st Shanethegamer 🇺🇸 770 157 149ms 8 Oct 2022 692nd primo-ppcg 🇹🇭 768 67 20ms 24 Jan 2022 693rd Shanethegamer 🇺🇸 768 99 90ms 12 Dec 2022 694th jmerle 🇳🇱 768 115 9ms 22 Jan 2022 694th PiterAnnema 768 115 16ms 23 Mar 2022 694th AGoyet 768 115 9ms 29 Jun 2022 694th Eilonlif 🇮🇱 768 115 10ms 11 Sep 2022 694th IsmaelGSerrano 768 115 10ms 2 Nov 2022 694th bobbysq 768 115 9ms 22 Jan 2023 694th msbranicky 768 115 9ms 25 Jul 2023 694th ArenaGrenade 768 115 10ms 19 Feb 2024 694th NickTheEASDude 🇺🇸 768 115 10ms 15 May 2024 694th dokutan 768 115 10ms 13 Aug 2024 694th maxgodfrey2004 🇨🇦 768 115 10ms 8 Jan 2025 694th Pyroan 768 115 9ms 21 Feb 2025 694th chartung17 768 115 10ms 24 Mar 2025 707th CatsAreFluffy 766 57 50ms 9 Jan 2023 707th xsot 🇸🇬 766 57 52ms 2 Feb 2024 709th iczelia 🇩🇪 766 123 1ms 24 Sep 2025 710th DialFrost 🇸🇬 765 71 42ms 26 Dec 2024 711th MeWhenI 🇻🇦 765 81 699ms 15 Sep 2025 712th edsrzf 🇳🇿 765 107 73ms 28 Jun 2025 713th GrayJoKing 🇦🇺 765 126 421ms 1 Mar 2022 714th Andrey-Plotnikov 764 93 9ms 21 Jun 2025 714th Protothor 764 93 9ms 9 Jul 2025 716th DialFrost 🇸🇬 764 133 6ms 11 Dec 2024 717th kejcao 🇨🇦 764 147 193ms 3 Aug 2024 718th jerrandolph 764 174 251ms 20 Oct 2023 719th stefangimmillaro 763 102 99ms 19 Oct 2022 720th annaproxy 763 134 13ms 24 Dec 2022 First Prev 641–720 of 1,567 Next Last
