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 Bytes Time Submitted 401st GrayJoKing 🇦🇺 847 130 3ms 12 Sep 2022 402nd xsot 🇸🇬 846 55 3ms 6 Jul 2025 403rd didion0 🇺🇸 846 84 8ms 25 Jan 2022 403rd 13x1 🇩🇪 846 84 10ms 15 May 2023 403rd biocommando 🇫🇮 846 84 10ms 11 Aug 2023 403rd deancureton 846 84 10ms 29 Dec 2024 403rd CaedenHarper 🇨🇦 846 84 10ms 22 Aug 2025 403rd solisolu 846 84 9ms 25 days ago 409th Shanethegamer 🇺🇸 846 90 3,884ms 28 Oct 2024 410th GrayJoKing 🇦🇺 846 115 9ms 28 Jul 2023 411th ovs-code 🇩🇪 845 114 439ms 26 Nov 2024 412th kaascevich 845 123 110ms 21 Jul 2025 413th lynn 844 124 1,277ms 16 Jan 2022 414th clockworknazo 843 62 2ms 17 Nov 2022 415th DialFrost 🇸🇬 843 66 274ms 10 Oct 2024 416th HumanoidCPU 843 127 573ms 8 Nov 2025 417th Sakisan 🇧🇪 842 64 53ms 30 Jun 2022 418th MeWhenI 🇻🇦 842 158 291ms 7 Jan 2025 419th ovs-code 🇩🇪 842 224 476ms 18 Apr 2025 420th TFeld00 🇩🇰 841 105 9ms 19 May 2022 420th stefangimmillaro 841 105 10ms 26 Dec 2022 420th betaveros 841 105 10ms 1 Jan 2023 420th 5cw 🇺🇸 841 105 9ms 3 May 2023 420th minhtrancccp 841 105 9ms 26 Sep 2023 420th lifthrasiir 🇰🇷 841 105 10ms 20 Nov 2024 420th Emutis 🇱🇹 841 105 9ms 4 Feb 2025 420th qpwoeirut 841 105 10ms 28 Sep 2025 428th Shanethegamer 🇺🇸 841 112 2ms 20 Apr 2022 429th Shanethegamer 🇺🇸 840 89 135ms 8 Jan 2025 429th emplv 🇱🇻 840 89 129ms 28 Mar 2025 429th ovs-code 🇩🇪 840 89 132ms 17 Apr 2025 432nd Shanethegamer 🇺🇸 840 92 363ms 26 Mar 2024 433rd jacobly0 🇺🇸 840 176 1,723ms 22 Apr 2024 434th neel11235813 839 91 368ms 13 Mar 2024 434th kg583 🇺🇸 839 91 478ms 21 Mar 2024 434th bizy-coder 839 91 378ms 1 Apr 2024 434th MeWhenI 🇻🇦 839 91 400ms 24 May 2024 434th duckyluuk 🇳🇱 839 91 376ms 21 Jun 2024 434th AlephSquirrel 839 91 393ms 3 Jul 2024 434th CaedenHarper 🇨🇦 839 91 384ms 18 days ago 441st SirBogman 🇺🇸 838 37 2ms 27 May 2024 441st emgordon154 838 37 59ms 11 Sep 2024 441st Yewzir 🇧🇪 838 37 2ms 19 Dec 2024 444th 4hg 🇺🇸 837 52 33ms 26 Jul 2023 445th DialFrost 🇸🇬 837 91 4,723ms 25 Oct 2024 446th GrayJoKing 🇦🇺 837 152 29ms 18 Jul 2023 447th MeWhenI 🇻🇦 836 65 49ms 7 Dec 2023 448th Natanaelel 🇸🇪 836 85 9ms 7 Feb 2023 448th HumanoidCPU 836 85 10ms 2 Mar 2025 450th edsrzf 🇳🇿 836 97 68ms 7 Oct 2025 451st Shanethegamer 🇺🇸 836 159 257ms 20 Apr 2022 452nd JayXon 🇺🇸 835 98 77ms 9 Apr 2023 453rd jacobly0 🇺🇸 835 104 2ms 11 Sep 2023 454th drabart 🇵🇱 834 132 69ms 16 Dec 2023 455th Bulmenisaurus 833 106 10ms 2 Feb 2025 456th Yewzir 🇧🇪 833 113 2ms 29 Nov 2023 456th drabart 🇵🇱 833 113 2ms 18 Dec 2023 458th dcgjb 831 67 259ms 14 Feb 2024 459th DialFrost 🇸🇬 831 90 129ms 3 Nov 2024 460th prplz 🇦🇺 831 93 363ms 18 Jan 2022 460th hemphen 831 93 342ms 28 Aug 2022 460th feberhard 831 93 362ms 6 Apr 2023 460th sean-niemann 🇺🇸 831 93 401ms 19 Apr 2025 464th emplv 🇱🇻 831 160 257ms 6 Jan 2023 464th KasperKivimaeki 🇫🇮 831 160 285ms 20 Oct 2025 466th jared-hughes 831 200 10ms 18 Dec 2024 467th Shanethegamer 🇺🇸 830 63 2ms 13 May 2023 468th pardouin 🇫🇷 830 71 981ms 2 Sep 2025 469th inventshah 830 92 406ms 21 Jan 2024 469th GolfingSuccess 🇬🇷 830 92 391ms 2 Mar 2024 471st emplv 🇱🇻 830 101 5ms 3 Jul 2023 471st stefangimmillaro 830 101 5ms 12 Oct 2023 471st edsrzf 🇳🇿 830 101 5ms 7 Oct 2025 474th Shanethegamer 🇺🇸 828 107 122ms 24 May 2025 475th Alex-x90 🇺🇸 828 133 71ms 8 Aug 2023 475th Yewzir 🇧🇪 828 133 71ms 29 Nov 2023 475th albanian-laundromat 828 133 3ms 22 Sep 2025 478th acotis 828 146 174ms 30 May 2025 479th Mandrzejy 🇵🇱 826 114 2ms 13 Sep 2024 479th AZTECCO 826 114 2ms 16 Sep 2025 First Prev 401–480 of 1,566 Next Last