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Calendar
hole will go live in approximately
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. Why not try and solve it ahead of time?
Recent Solutions
Achievements
Cheevos
Golfers
Solutions
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
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><>
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
Hole
Golfer
Bytes
Time
Submitted
Trinomial Triangle
dokutan
1,236
116ms
3 hours ago
Sierpiński Triangle
dokutan
212
115ms
3 hours ago
Rijndael S-box
dokutan
652
108ms
3 hours ago
Polyominoes
dokutan
🥉
980
117ms
3 hours ago
Number Spiral
dokutan
304
112ms
3 hours ago
N Queens
dokutan
🥉
748
115ms
3 hours ago
Mandelbrot
dokutan
348
119ms
3 hours ago
Leyland Numbers
dokutan
684
120ms
3 hours ago
Kaprekar Numbers
dokutan
392
119ms
3 hours ago
Hilbert Curve
dokutan
💎
488
115ms
3 hours ago
Hexagonal Spiral
dokutan
320
114ms
3 hours ago
Factorial Factorisation
dokutan
584
116ms
3 hours ago
Diamonds
dokutan
192
112ms
3 hours ago
Cubes
dokutan
572
118ms
3 hours ago
Catalan Numbers
dokutan
2,056
114ms
3 hours ago
24 Game
dokutan
4,296
127ms
3 hours ago
12 Days of Christmas
dokutan
512
120ms
3 hours ago
Rule 110
dokutan
1,300
111ms
3 hours ago
Tower of Hanoi
KatieLG
368
104ms
28 hours ago
Fizz Buzz
mwarvik
82
106ms
29 hours ago
Fibonacci
albanian-laundromat
54
105ms
3 days ago
Hexagonal Spiral
bitsandbeyond
270
106ms
4 days ago
Tower of Hanoi
JayXon
🥇
65
103ms
8 days ago
Leap Years
edsrzf
🥇
52
115ms
8 days ago
Pangram Grep
kmathis22
138
131ms
9 days ago
Divisors
Yax42
99
118ms
12 days ago
γ
JOrE20
1,020
110ms
12 days ago
Tongue-twisters
prestosilver
553
101ms
12 days ago
Happy Numbers (Long)
snoozingnewt
141
106ms
14 days ago
Arrows
dokutan
627
127ms
16 days ago
Day of Week
snoozingnewt
🥇
110
133ms
17 days ago
Odious Numbers (Long)
snoozingnewt
🥇
49
103ms
18 days ago
Odious Numbers
snoozingnewt
🥇
48
100ms
18 days ago
Evil Numbers
snoozingnewt
🥇
48
103ms
18 days ago
Evil Numbers (Long)
snoozingnewt
🥇
50
103ms
18 days ago
Prime Numbers
tomh1012
84
99ms
18 days ago
Arrows
snoozingnewt
137
141ms
19 days ago
λ
sean-niemann
🥈
239
194ms
21 days ago
Zeckendorf Representation
sean-niemann
102
104ms
23 days ago
Scrambled Sort
snoozingnewt
🥉
162
109ms
23 days ago
Tower of Hanoi
dokutan
77
107ms
23 days ago
Niven Numbers
snoozingnewt
🥇
53
104ms
25 days ago
Pernicious Numbers
snoozingnewt
🥇
47
103ms
26 days ago
Star Wars Opening Crawl
albanian-laundromat
🥈
496
122ms
26 days ago
Lucky Numbers
sean-niemann
🥈
77
115ms
26 days ago
Tower of Hanoi
DialFrost
67
104ms
27 days ago
Tower of Hanoi
sean-niemann
🥇
65
110ms
1 Dec 2025
Spelling Numbers
dokutan
🥉
1,026
122ms
1 Dec 2025
Lucky Tickets
dokutan
5,318
109ms
1 Dec 2025
Van Eck Sequence
KatieLG
1,727
103ms
30 Nov 2025
Vampire Numbers
KatieLG
1,058
105ms
30 Nov 2025
Trinomial Triangle
KatieLG
1,873
104ms
30 Nov 2025
Tongue-twisters
KatieLG
516
107ms
30 Nov 2025
Smith Numbers
KatieLG
1,676
105ms
30 Nov 2025
Sierpiński Triangle
KatieLG
243
105ms
30 Nov 2025
Rule 110
KatieLG
2,132
103ms
30 Nov 2025
Recamán
KatieLG
824
104ms
30 Nov 2025
Prime Numbers (Long)
KatieLG
4,374
107ms
30 Nov 2025
Polyominoes
KatieLG
1,393
102ms
30 Nov 2025
Pernicious Numbers (Long)
KatieLG
14,227
110ms
30 Nov 2025
Pascal’s Triangle
KatieLG
711
106ms
30 Nov 2025
Odious Numbers (Long)
KatieLG
1,694
107ms
30 Nov 2025
Niven Numbers (Long)
KatieLG
5,671
105ms
30 Nov 2025
N Queens
KatieLG
1,210
102ms
30 Nov 2025
Mandelbrot
KatieLG
624
106ms
30 Nov 2025
Lucky Numbers
KatieLG
3,809
104ms
30 Nov 2025
Look and Say
KatieLG
738
106ms
30 Nov 2025
Leap Years
KatieLG
628
106ms
30 Nov 2025
Kolakoski Sequence
KatieLG
367
108ms
30 Nov 2025
Inventory Sequence
KatieLG
1,785
106ms
30 Nov 2025
Hilbert Curve
KatieLG
983
106ms
30 Nov 2025
Gijswijt’s Sequence
KatieLG
279
111ms
30 Nov 2025
Foo Fizz Buzz Bar
KatieLG
1,587
105ms
30 Nov 2025
Fizz Buzz
KatieLG
296
105ms
30 Nov 2025
Farey Sequence
KatieLG
2,968
107ms
30 Nov 2025
Factorial Factorisation
KatieLG
826
105ms
30 Nov 2025
Evil Numbers (Long)
KatieLG
1,698
102ms
30 Nov 2025
Emirp Numbers (Long)
KatieLG
1,040
107ms
30 Nov 2025
Divisors
KatieLG
861
103ms
30 Nov 2025
Diamonds
KatieLG
427
97ms
30 Nov 2025