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 641st MeWhenI 🇻🇦 741 129 424ms 4 Aug 2023 642nd BREMAUCY 🇫🇷 741 316 13ms 3 days ago 643rd primo-ppcg 🇹🇭 740 144 409ms 4 Apr 2022 643rd Lydxn 🇨🇦 740 144 676ms 5 Apr 2022 643rd rotary-o 🇯🇵 740 144 578ms 5 May 2023 643rd Steffan153 🇫🇮 740 144 402ms 24 Feb 2024 643rd Jacob385 740 144 550ms 28 Oct 2025 648th bac0id 740 148 71ms 3 Jul 2024 649th HumanoidCPU 739 179 278ms 3 Mar 2025 650th MeWhenI 🇻🇦 738 123 333ms 30 Jan 2023 651st Shanethegamer 🇺🇸 737 111 106ms 14 days ago 652nd ovs-code 🇩🇪 736 70 2ms 8 Nov 2022 653rd 4hg 🇺🇸 736 79 950ms 8 Dec 2022 653rd anter69 🇭🇺 736 79 1,014ms 19 Feb 2023 653rd emgordon154 736 79 1,037ms 25 Nov 2024 653rd Shanethegamer 🇺🇸 736 79 968ms 9 Apr 2025 657th BambooleanLogic 🇸🇪 736 96 9ms 20 Aug 2022 657th vroup 🇩🇰 736 96 9ms 2 Oct 2022 657th Ultra814 736 96 9ms 17 Aug 2025 657th tomh1012 736 96 9ms 27 days ago 661st SirBogman 🇺🇸 735 61 37ms 21 May 2022 661st Shanethegamer 🇺🇸 735 61 36ms 27 May 2022 661st canissimia 🇦🇶 735 61 44ms 18 Jul 2022 664th JunkIce 735 85 379ms 3 Dec 2024 665th BlankSpruce 735 149 68ms 16 Jan 2022 666th weliveinhell 🇭🇹 735 180 262ms 4 Oct 2023 666th emgordon154 735 180 264ms 20 Feb 2025 668th emplv 🇱🇻 735 182 25ms 31 Oct 2022 669th xnor-gate 734 94 16ms 30 Jul 2024 670th edsrzf 🇳🇿 734 164 311ms 29 Jul 2025 671st rucin93 🇵🇱 732 84 136ms 31 Oct 2024 672nd billings7 🇬🇧 732 105 353ms 12 Nov 2023 672nd MiffOttah 732 105 402ms 28 Nov 2024 674th jared-hughes 732 128 2ms 17 Mar 2022 675th SirBogman 🇺🇸 732 320 15ms 21 May 2022 676th JRaspass 🇬🇧 731 181 264ms 23 Sep 2022 677th Steffan153 🇫🇮 729 57 3ms 6 Jan 2023 677th Natanaelel 🇸🇪 729 57 3ms 13 May 2023 679th iczelia 🇩🇪 729 97 9ms 26 Sep 2025 679th johnkiernander 729 97 9ms 4 days ago 681st yzhs 🇩🇪 729 153 146ms 25 Jun 2023 682nd MeWhenI 🇻🇦 729 160 41ms 4 Sep 2024 683rd Yewzir 🇧🇪 728 137 38ms 28 Nov 2023 684th chunes3 🇺🇸 727 100 79ms 15 Sep 2023 684th Natanaelel 🇸🇪 727 100 70ms 8 Dec 2023 686th GeneralTwi 726 95 10ms 2 May 2022 687th retrohun 726 151 77ms 30 Dec 2022 687th annaproxy 726 151 67ms 5 Jan 2023 689th ericlangedijk 🇸🇮 725 106 352ms 19 Mar 2022 690th KenanSi 724 42 2ms 24 Feb 2022 690th Natanaelel 🇸🇪 724 42 2ms 21 Jun 2022 690th GolfingSuccess 🇬🇷 724 42 2ms 31 Dec 2022 693rd Shanethegamer 🇺🇸 724 161 41ms 13 Feb 2025 694th mlugg 724 203 1,617ms 10 Aug 2024 695th Natanaelel 🇸🇪 723 62 38ms 18 May 2025 696th AlephSquirrel 722 36 54ms 29 Dec 2022 697th Shanethegamer 🇺🇸 722 138 38ms 6 Sep 2022 698th GolfingSuccess 🇬🇷 721 80 5ms 17 Aug 2024 699th krcs 🇵🇱 721 98 9ms 2 May 2022 699th stefangimmillaro 721 98 8ms 12 Sep 2024 701st janbehrens 🇩🇪 721 130 5ms 23 Jun 2023 701st dokutan 721 130 1ms 8 Nov 2025 703rd jared-hughes 721 152 592ms 24 Jun 2022 703rd Betuaredead 721 152 465ms 7 Jan 2023 705th Shanethegamer 🇺🇸 720 180 40ms 23 Apr 2022 706th CheeseCake628 🇳🇴 718 87 359ms 17 Jan 2024 707th Jacob385 718 96 12ms 17 Sep 2024 708th janbehrens 🇩🇪 718 133 495ms 24 Nov 2022 709th MeWhenI 🇻🇦 717 139 40ms 17 Feb 2023 710th scpchicken 🇵🇼 716 58 3ms 22 Feb 2023 711th MeWhenI 🇻🇦 716 72 2ms 13 Nov 2022 712th dokutan 716 153 76ms 8 Nov 2025 713th msbranicky 716 168 147ms 1 Oct 2023 714th KasperKivimaeki 🇫🇮 715 149 343ms 6 days ago 714th ravnskjaer 🇩🇰 715 149 341ms 3 days ago 716th Frowny 715 156 146ms 11 Jan 2022 717th GeorgeStechman 🇬🇧 714 99 8ms 19 May 2022 717th vphoebe 714 99 9ms 25 May 2022 717th elisherer 🇮🇱 714 99 9ms 5 Jun 2022 720th ovs-code 🇩🇪 712 63 36ms 9 May 2023 First Prev 641–720 of 1,555 Next Last