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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
Chars
Time
Submitted
99 Bottles of Beer
prestosilver
283
404ms
25 mins ago
Arithmetic Numbers
prestosilver
83
530ms
75 mins ago
Inventory Sequence
prestosilver
83
120ms
113 mins ago
Prime Numbers (Long)
prestosilver
67
631ms
24 hours ago
Prime Numbers
prestosilver
65
119ms
24 hours ago
Arabic to Roman
prestosilver
185
333ms
25 hours ago
Tower of Hanoi
KatieLG
339
282ms
2 days ago
Arrows
BREMAUCY
208
355ms
4 days ago
Hexagonal Spiral
bitsandbeyond
260
126ms
6 days ago
Trinomial Triangle
edsrzf
🥇
94
131ms
8 days ago
Van Eck Sequence
HumanoidCPU
115
135ms
8 days ago
λ
JOrE20
1,008
143ms
9 days ago
Tower of Hanoi
JayXon
💎
59
127ms
9 days ago
Scrambled Sort
prestosilver
🥉
134
370ms
12 days ago
CSS Colors
prestosilver
🥇
59
361ms
12 days ago
Tower of Hanoi
prestosilver
99
130ms
12 days ago
ROT13
prestosilver
136
340ms
12 days ago
Evil Numbers
prestosilver
75
130ms
12 days ago
12 Days of Christmas
prestosilver
511
384ms
12 days ago
Collatz
prestosilver
74
124ms
13 days ago
γ
JOrE20
1,008
139ms
14 days ago
Day of Week
snoozingnewt
🥇
66
334ms
16 days ago
Day of Week
DialFrost
🥇
66
328ms
16 days ago
Odious Numbers (Long)
snoozingnewt
54
138ms
19 days ago
Odious Numbers
snoozingnewt
53
139ms
19 days ago
Evil Numbers
snoozingnewt
53
143ms
19 days ago
Evil Numbers (Long)
snoozingnewt
55
133ms
19 days ago
CSS Colors
FortuiteMan
🥇
59
345ms
23 days ago
CSS Colors
JOrE20
🥇
59
318ms
24 days ago
Pascal’s Triangle
edsrzf
75
118ms
24 days ago
CSS Colors
CornerMercury
🥇
59
332ms
24 days ago
Gray Code Decoder
albanian-laundromat
77
366ms
24 days ago
Niven Numbers
snoozingnewt
47
111ms
27 days ago
Pernicious Numbers
snoozingnewt
🥇
41
183ms
27 days ago
Tongue-twisters
prestosilver
532
173ms
27 days ago
PalindromemordnilaP
edsrzf
99
553ms
1 Dec 2025
Spelling Numbers
dokutan
874
596ms
1 Dec 2025
Lucky Tickets
dokutan
4,778
483ms
1 Dec 2025
Tower of Hanoi
edsrzf
🥈
62
181ms
1 Dec 2025
Van Eck Sequence
KatieLG
1,685
291ms
30 Nov 2025
Vampire Numbers
KatieLG
1,048
291ms
30 Nov 2025
Trinomial Triangle
KatieLG
1,841
273ms
30 Nov 2025
Tongue-twisters
KatieLG
510
284ms
30 Nov 2025
Smith Numbers
KatieLG
1,651
290ms
30 Nov 2025
Sierpiński Triangle
KatieLG
231
303ms
30 Nov 2025
Rule 110
KatieLG
2,040
297ms
30 Nov 2025
Recamán
KatieLG
815
309ms
30 Nov 2025
Proximity Grid
KatieLG
3,573
359ms
30 Nov 2025
Prime Numbers (Long)
KatieLG
4,256
305ms
30 Nov 2025
Polyominoes
KatieLG
1,346
289ms
30 Nov 2025
Pernicious Numbers (Long)
KatieLG
14,000
297ms
30 Nov 2025
Pascal’s Triangle
KatieLG
704
276ms
30 Nov 2025
Odious Numbers (Long)
KatieLG
1,666
283ms
30 Nov 2025
Niven Numbers (Long)
KatieLG
5,502
281ms
30 Nov 2025
N Queens
KatieLG
1,186
280ms
30 Nov 2025
Mandelbrot
KatieLG
577
279ms
30 Nov 2025
Lucky Numbers
KatieLG
3,690
286ms
30 Nov 2025
Look and Say
KatieLG
711
283ms
30 Nov 2025
Kolakoski Sequence
KatieLG
351
285ms
30 Nov 2025
Inventory Sequence
KatieLG
1,725
292ms
30 Nov 2025
Hilbert Curve
KatieLG
876
300ms
30 Nov 2025
Gijswijt’s Sequence
KatieLG
257
284ms
30 Nov 2025
Foo Fizz Buzz Bar
KatieLG
1,529
290ms
30 Nov 2025
Fizz Buzz
KatieLG
289
283ms
30 Nov 2025
Farey Sequence
KatieLG
2,866
289ms
30 Nov 2025
Factorial Factorisation
KatieLG
815
284ms
30 Nov 2025
Evil Numbers (Long)
KatieLG
1,670
278ms
30 Nov 2025
Emirp Numbers (Long)
KatieLG
1,026
279ms
30 Nov 2025
Divisors
KatieLG
845
293ms
30 Nov 2025
Diamonds
KatieLG
397
277ms
30 Nov 2025
Cubes
KatieLG
835
279ms
30 Nov 2025
Collatz
KatieLG
2,185
298ms
30 Nov 2025
Christmas Trees
KatieLG
315
292ms
30 Nov 2025
Catalan Numbers
KatieLG
2,630
292ms
30 Nov 2025
Ascending Primes
KatieLG
464
291ms
30 Nov 2025
Arithmetic Numbers
KatieLG
24,576
304ms
30 Nov 2025
Abundant Numbers (Long)
KatieLG
850
292ms
30 Nov 2025
99 Bottles of Beer
KatieLG
1,293
291ms
30 Nov 2025
24 Game
KatieLG
5,059
285ms
30 Nov 2025
12 Days of Christmas
KatieLG
2,081
281ms
30 Nov 2025