Rosetta Code/Count examples/Full list/Tier 2

From Rosetta Code

Second tier of languages sorted by number of examples completed.

See Rosetta_Code/Rank_languages_by_popularity/Full_list for a full language/task completion table.

Top tier Second tier Third tier Fourth tier
Second ten programming languages by number of task examples completed:
    ⑪ C             ⑫ C++           ⑬ Ruby          ⑭ FreeBASIC     ⑮ Mathematica  
    ⑯ Haskell       ⑰ REXX          ⑱ Kotlin        ⑲ Racket        ⑳ Jq           
As of 2023-12-10T22:02:57Z :: Tasks: 1261 :: Draft Tasks:399 :: Total Tasks: 1660 :: Total Examples: 94449
Count Task
585 Hello world/Text
377 FizzBuzz
374 99 bottles of beer
352 100 doors
304 Comments
303 Factorial
302 Fibonacci sequence
296 A+B
288 Empty program
256 Loops/Infinite
248 Reverse a string
246 Arrays
244 Function definition
242 Ackermann function
237 Loops/For
232 Loops/While
229 Conditional structures
222 Array concatenation
217 Arithmetic/Integer
213 Greatest element of a list
204 Increment a numerical string
204 Repeat a string
203 Even or odd
202 Greatest common divisor
200 Sieve of Eratosthenes
199 Array length
197 Averages/Arithmetic mean
195 Hello world/Graphical
194 Binary digits
192 Copy a string
191 String concatenation
190 Towers of Hanoi
189 Loops/Downward for
189 Sum and product of an array
188 Boolean values
188 Integer comparison
186 Hello world/Newline omission
186 Rot-13
185 Apply a callback to an array
185 Integer sequence
184 Character codes
184 Loops/For with a specified step
183 Palindrome detection
181 String length
180 String case
180 Tokenize a string
178 Loops/Break
178 Loops/Foreach
177 Empty string
176 Sum of a series
175 Quine
173 Dot product
173 Sum of squares
172 Filter
172 Logical operations
169 Loops/Do-while
168 Hailstone sequence
163 Loops/N plus one half
162 Associative array/Creation
162 Generic swap
161 Sorting algorithms/Quicksort
160 Caesar cipher
159 Leap year
159 Sort an integer array
156 Command-line arguments
156 Generate lower case ASCII alphabet
155 Determine if a string is numeric
155 Execute a system command
155 Luhn test of credit card numbers
155 System time
154 User input/Text
153 Factors of an integer
152 Hello world/Standard error
152 Higher-order functions
152 Loops/Continue
152 Stack
152 Zero to the zero power
150 ABC problem
150 Loop over multiple arrays simultaneously
149 Guess the number
148 Bitwise operations
148 Read entire file
148 Sorting algorithms/Bubble sort
147 Primality by trial division
147 Remove duplicate elements
146 Check that file exists
146 Create a file
146 Mutual recursion
145 Balanced brackets
145 Count in octal
144 Ethiopian multiplication
144 Least common multiple
144 Roman numerals/Encode
144 Sleep
142 File input/output
142 Mandelbrot set
141 Program termination
140 Day of the week
140 Happy numbers
140 Literals/String
139 Literals/Integer
138 Date format
138 Pascal's triangle
138 Substring
138 Variables
137 Count occurrences of a substring
135 Compound data type
134 Knuth shuffle
134 Loops/Nested
133 Function composition
133 Include a file
133 Pick random element
132 Babbage problem
132 Sorting algorithms/Insertion sort
131 Align columns
131 Matrix transposition
131 N-queens problem
131 String matching
130 Averages/Median
130 Detect division by zero
130 Letter frequency
130 Null object
130 Real constants and functions
129 Averages/Root mean square
129 File size
129 Strip a set of characters from a string
128 Guess the number/With feedback
128 Look-and-say sequence
128 Read a file line by line
128 Return multiple values
128 String append
127 Anagrams
127 Associative array/Iteration
127 Binary search
127 Delete a file
126 Matrix multiplication
126 Perfect numbers
125 Conway's Game of Life
125 Flatten a list
125 Hash from two arrays
125 Identity matrix
124 Haversine formula
124 Input loop
123 Case-sensitivity of identifiers
123 Environment variables
123 Harshad or Niven series
122 Call a function
122 Find limit of recursion
122 Roman numerals/Decode
121 Classes O O
121 Sierpinski triangle
120 Assertions
120 Pangram checker
119 Bulls and cows
119 Levenshtein distance
119 Run-length encoding
119 Search a list
119 String interpolation (included)
119 Substring/Top and tail
118 HTTP
118 Rename a file
118 Variadic function
117 Arithmetic/Complex
117 Comma quibbling
117 Formatted numeric output
117 Multiplication tables
117 Sum multiples of 3 and 5
116 Horner's rule for polynomial evaluation
116 Infinity
116 Strip whitespace from a string/Top and tail
115 Evaluate binomial coefficients
115 Hostname
115 Ordered words
114 Accumulator factory
114 Averages/Pythagorean means
114 Reverse words in a string
114 Sum digits of an integer
114 The Twelve Days of Christmas
113 Anonymous recursion
113 Create a two-dimensional array at runtime
113 Permutations
113 Program name
113 Sequence of non-squares
112 Digital root
112 Sorting algorithms/Merge sort
112 String prepend
112 Zig-zag matrix
111 Calculating the value of e
111 Catalan numbers
111 Combinations
111 Middle three digits
110 Exceptions
110 Queue/Definition
110 Random numbers
110 Trigonometric functions
109 Amicable pairs
109 Temperature conversion
108 Abundant, deficient and perfect number classifications
108 Shell one-liner O
108 Short-circuit evaluation
108 Time a function
108 Vector products
107 Arbitrary-precision integers (included)
107 Arithmetic-geometric mean
106 24 game
106 Enumerations
106 Hello world/Newbie
106 Prime decomposition
105 Evolutionary algorithm
105 Regular expressions
105 Show ASCII table
105 Symmetric difference
104 Power set
104 Sorting algorithms/Selection sort
103 Averages/Mode
103 Hofstadter Q sequence
103 Tree traversal
103 Walk a directory/Non-recursively
102 Collections
102 Gray code
102 N'th
101 Exponentiation operator
101 Interactive programming (repl) O O
101 Map range
101 Nth root
100 Create an HTML table
100 Sort using a custom comparator
99 Execute Brain****
99 Hamming numbers
99 Modular inverse
99 Monty Hall problem
99 Range expansion
99 String comparison
99 Y combinator
98 Entropy
98 First-class functions
98 MD5
98 Random number generator (included)
97 Address of a variable O O
97 Langton's ant
97 Number reversal game
97 Sorting algorithms/Cocktail sort
97 Sorting algorithms/Heapsort
96 Catamorphism
96 Forward difference
96 Menu
96 Sierpinski carpet
96 Sorting algorithms/Bogosort
95 Compare a list of strings
95 Inheritance/Single O
95 JSON
95 Range extraction
95 Sorting algorithms/Gnome sort
95 Split a character string based on change of character
95 Terminal control/Clear the screen
94 Averages/Simple moving average
94 Cumulative standard deviation
94 Last Friday of each month
94 Number names
94 One-dimensional cellular automata
93 Abstract type
93 Almost prime
93 Anti-primes
93 CSV data manipulation
93 Floyd's triangle
93 Greatest subsequential sum
93 Repeat
93 Simple windowed application
92 Five weekends
92 Literals/Floating point
92 Multifactorial
91 Box the compass
91 Count in factors
91 Non-decimal radices/Convert
91 Population count
91 Set
90 Hello world/Line printer
90 Long multiplication
90 Munchausen numbers
90 Operator precedence
90 URL decoding
90 Window creation
89 CSV to HTML translation
89 Count the coins
89 Department numbers
89 Find the last Sunday of each month
89 Playing cards
89 Queue/Usage
89 Sort an array of composite structures
89 Word wrap
88 Bitmap
88 Find common directory path
88 Josephus problem
88 Order two numerical lists
88 Price fraction
88 Proper divisors
88 SEDOLs
88 Strip comments from a string
88 Top rank per group
88 Walk a directory/Recursively
87 15 puzzle game
87 CRC-32
87 Closures/Value capture
87 Here document O
87 Read a specific line from a file
87 Terminal control/Ringing the terminal bell
87 URL encoding
86 Additive primes
86 File modification time
86 Jump anywhere
86 Singly-linked list/Traversal
85 100 prisoners
85 Angle difference between two bearings
85 Attractive numbers
85 Call an object method O O
85 Extend your language O
85 Introspection
85 Jensen's Device
85 Knapsack problem/0-1
85 Lucas-Lehmer test
85 Sorting algorithms/Shell sort
85 Thue-Morse
84 Convert seconds to compound duration
84 Dynamic variable names O O
84 Find the missing permutation
84 Monte Carlo methods
84 Priority queue
84 Pythagorean triples
84 Spiral matrix
83 Dragon curve
83 Fibonacci n-step number sequences
83 Kaprekar numbers
83 Keyboard input/Obtain a Y or N response
83 Man or boy test
83 Pi
83 Sequence of primes by trial division
83 Show the epoch
83 Sockets
83 Sorting algorithms/Counting sort
83 Soundex
83 Take notes on the command line
82 Animation
82 Benford's law
82 Concurrent computing
82 Linear congruential generator
82 Old lady swallowed a fly
82 Pernicious numbers
82 Sort disjoint sublist
82 Special characters
82 Unicode variable names
82 Web scraping
82 XML/Input
81 Anagrams/Deranged anagrams
81 Call a foreign-language function
81 Date manipulation
81 Empty directory
81 Equilibrium index
81 Gamma function
81 Phrase reversals
81 Singly-linked list/Element definition
81 Sorting algorithms/Comb sort
81 Vigenère cipher
81 Write entire file
80 Averages/Mean angle
80 Calendar
80 Currying
80 Exponentiation order
80 Flow-control structures
80 Fractal tree
80 Quaternion type
80 Rep-string
80 Rock-paper-scissors
80 Semordnilap
79 AKS test for primes
79 Draw a sphere
79 Four bit adder
79 Guess the number/With feedback (player)
79 Hello world/Web server
79 Jewels and stones
79 List comprehensions
79 Non-decimal radices/Output
79 SHA-1
79 Sudoku
78 Chinese remainder theorem
78 Execute HQ9+
78 Read a configuration file
78 Semiprime
77 Bitmap/Bresenham's line algorithm
77 Catalan numbers/Pascal's triangle
77 Damm algorithm
77 Enforced immutability
77 Euler method
77 I before E except after C
77 Self-describing numbers
77 Sort three variables
77 Unix/ls
77 Van der Corput sequence
77 Write float arrays to a text file
77 Zeckendorf number representation
76 Combinations with repetitions
76 Exceptions/Catch an exception thrown in a nested call
76 General FizzBuzz
76 Largest int from concatenated ints
76 McNuggets problem
76 Roots of unity
76 Sorting algorithms/Stooge sort
76 Van Eck sequence
76 Yin and yang
75 ISBN13 check digit
75 Maze generation
75 Multiple distinct objects
75 Parsing/RPN calculator algorithm
75 SHA-256
75 Special variables
75 Stair-climbing puzzle
75 Stern-Brocot sequence
75 Strip control codes and extended characters from a string
74 4-rings or 4-squares puzzle
74 Amb
74 Constrained random points on a circle
74 Continued fraction
74 Narcissistic decimal number
74 Nested function
74 Numerical integration
74 Runtime evaluation O O O
74 Square but not cube
74 Trabb Pardo–Knuth algorithm
73 Barnsley fern
73 Isqrt (integer square root) of X
73 Longest common subsequence
73 Named parameters
73 Polymorphism O
73 Variable size/Get
72 Abundant odd numbers
72 Arithmetic/Rational
72 Closest-pair problem
72 Compile-time calculation O
72 Determine if a string is collapsible
72 Fast Fourier transform
72 IBAN
72 Leonardo numbers
72 Magic 8-ball
72 Magic squares of odd order
72 Morse code
72 Probabilistic choice
72 Sorting algorithms/Pancake sort
72 Subleq
72 Text processing/Max licenses in use
72 Word frequency
71 Circles of given radius through two points
71 Euler's sum of powers conjecture
71 Get system command output
71 Modular exponentiation
71 RPG attributes generator
71 Singly-linked list/Element insertion
71 Two sum
70 Best shuffle
70 Binary strings
70 Chinese zodiac
70 Dutch national flag problem
70 Host introspection
70 Memory allocation
70 One of n lines in a file
70 Remove lines from a file
70 Roots of a function
70 Smith numbers
70 Sort stability
70 Tau function
69 Animate a pendulum
69 Arithmetic evaluation
69 Cartesian product of two or more lists
69 Cholesky decomposition
69 Emirp primes
69 Extract file extension
69 Fork
69 Integer overflow
69 Mouse position
69 Reduced row echelon form
69 Remove vowels from a string
69 Two identical strings
69 Write language name in 3D ASCII
68 CUSIP
68 Disarium numbers
68 Documentation
68 Draw a clock
68 Draw a cuboid
68 Factors of a Mersenne number
68 Long year
68 Miller–Rabin primality test
68 Non-decimal radices/Input
68 Plot coordinate pairs
68 Roots of a quadratic function
68 Runge-Kutta method
68 Sorting algorithms/Sleep sort
68 XML/Output
67 9 billion names of God the integer
67 Base64 decode data
67 Cantor set
67 Determine if a string has all the same characters
67 Globally replace text in several files
67 HTTPS
67 Longest common substring
67 Optional parameters
67 Quickselect algorithm
67 Tic-tac-toe
67 Undefined values
66 Averages/Mean time of day
66 Draw a pixel
66 Hofstadter-Conway $10,000 sequence
66 Inheritance/Multiple O
66 Longest common prefix
66 Maximum triangle path sum
66 Terminal control/Display an extended character
66 Test a function
66 Totient function
66 Vector
65 2048
65 Base64 encode data
65 Bitmap/Write a PPM file
65 Farey sequence
65 Knapsack problem/Continuous
65 Knapsack problem/Unbounded
65 Knight's tour
65 Ludic numbers
65 Pascal matrix generation
65 Ternary logic
64 24 game/Solve
64 Copy stdin to stdout
64 DNS query O
64 FASTA format
64 Gapful numbers
64 Generator/Exponential
64 Huffman coding
64 JortSort
64 Loops/Increment loop index within loop body
64 Primality by Wilson's theorem
64 Tau number
64 Truncatable primes
64 Unicode strings
63 Brownian tree
63 Discordian date
63 Fusc sequence
63 Horizontal sundial calculations
63 Left factorials
63 Partial function application
63 Sattolo cycle
63 Sum of first n cubes
62 Add a variable to a class instance at runtime O O O
62 Archimedean spiral
62 Grayscale image
62 Iterated digits squaring
62 Kernighans large earthquake problem
62 Mad Libs
62 Matrix-exponentiation operator
62 Nim game
62 Odd word problem O
62 Sum of divisors
62 Terminal control/Coloured text
61 Code Golf: Code Golf
61 Convert decimal number to rational
61 Deal cards for FreeCell
61 Define a primitive data type O O
61 Dinesman's multiple-dwelling problem
61 Doubly-linked list/Element definition
61 Fibonacci word
61 LZW compression
61 Largest proper divisor of n
61 Loops/With multiple ranges
61 Random number generator (device)
61 Scope modifiers
61 Sorting algorithms/Bead sort
61 Topological sort
61 Truncate a file
61 User input/Graphical
60 Bernoulli numbers
60 Hash join
60 Inverted syntax
60 Keyboard input/Keypress check
60 Multisplit
60 Perfect shuffle
60 Pig the dice game
60 Pointers and references O O
60 Stem-and-leaf plot
60 Unbias a random generator
60 Words containing "the" substring
59 Bell numbers
59 Call a function in a shared library
59 Days between dates
59 Dijkstra's algorithm
59 Find the intersection of two lines
59 Forest fire
59 Holidays related to Easter
59 Runtime evaluation/In an environment O O
59 Shoelace formula for polygonal area
59 Singleton O O
59 Sorting algorithms/Permutation sort
59 Tokenize a string with escaping
59 Universal Turing machine
58 Abbreviations, automatic
58 Associative array/Merging
58 Chaos game
58 Delegates
58 Extreme floating point values
58 First-class functions/Use numbers analogously O
58 Modulinos
58 Recaman's sequence
58 Rosetta Code/Rank languages by popularity
58 Seven-sided dice from five-sided dice
58 Sort numbers lexicographically
58 Stack traces
58 Statistics/Basic
57 Bioinformatics/base count
57 Determine if a string has all unique characters
57 Handle a signal O
57 Heronian triangles
57 Kronecker product
57 Longest string challenge
57 Naming conventions
57 Password generator
57 Perfect totient numbers
57 Search a list of records
57 Sierpinski triangle/Graphical
57 Strange plus numbers
57 Validate International Securities Identification Number
57 XML/XPath
56 Compare length of two strings
56 Egyptian division
56 Extensible prime generator
56 Fractran
56 Hofstadter Figure-Figure sequences
56 Non-continuous subsequences
56 Polynomial regression
56 Rate counter
56 Strip block comments
56 Ulam spiral (for primes)
56 Water collected between towers
56 Wireworld
55 Halt and catch fire
55 Longest increasing subsequence
55 Move-to-front algorithm
55 Munching squares
55 Send email
55 Synchronous concurrency
55 Terminal control/Cursor positioning
55 Text processing/2
55 XML/DOM serialization
54 Determine if a string is squeezable
54 Doubly-linked list/Element insertion
54 Elementary cellular automaton
54 Gaussian elimination
54 Generate Chess960 starting position
54 Greyscale bars/Display
54 Idiomatically determine all the lowercase and uppercase letters
54 Jaro similarity
54 Mertens function
54 Odd and square numbers
54 Smallest square that begins with n
54 Spinning rod animation/Text
54 The Name Game
54 Zebra puzzle
53 21 game
53 Aliquot sequence classifications
53 Average loop length
53 Convex hull
53 Digital root/Multiplicative digital root
53 Dining philosophers
53 Doubly-linked list/Traversal
53 Execute a Markov algorithm
53 Hilbert curve
53 Image noise
53 MAC vendor lookup
53 Make directory path
53 Musical scale
53 Sum of the digits of n is substring of n
52 Append a record to the end of a text file
52 Casting out nines
52 Determinant and permanent
52 Find words which contains more than 3 e vowels
52 GUI component interaction
52 Metaprogramming
52 Numbers divisible by their individual digits, but not by the product of their digits.
52 Polynomial long division
52 Stable marriage problem
52 Text between
52 Text processing/1
51 ABC words
51 Bitmap/Flood fill
51 Chowla numbers
51 Colour bars/Display
51 Colour pinstripe/Display
51 Currency
51 Doubly-linked list/Definition
51 History variables O
51 Permutations/Derangements
51 Respond to an unknown method call O
51 Set consolidation
51 Strange numbers
51 Taxicab numbers
50 Abbreviations, easy
50 Approximate equality
50 Bitmap/Midpoint circle algorithm
50 Floyd-Warshall algorithm
50 Humble numbers
50 Last letter-first letter
50 Matrix with two diagonals
50 Polymorphic copy O
50 Send an unknown method call O O
50 Sequence: smallest number with exactly n divisors
50 Sparkline in unicode
50 Start from a main routine O O
50 Substitution cipher
50 Variable size/Set O
50 Verify distribution uniformity/Naive
50 Visualize a tree
49 Active object
49 Bitmap/Read a PPM file
49 Brazilian numbers
49 Coprimes
49 Deepcopy O
49 Element-wise operations
49 Find square difference
49 OpenGL
49 Problem of Apollonius
49 Sorting algorithms/Radix sort
49 Twelve statements
49 UTF-8 encode and decode
48 Bulls and cows/Player
48 Color of a screen pixel
48 Combinations and permutations
48 Continued fraction/Arithmetic/Construct from rational number
48 Determine if only one instance is running
48 Feigenbaum constant calculation
48 File extension is in extensions list
48 GUI/Maximum window dimensions
48 Julia set
48 Magnanimous numbers
48 Narcissist
48 Parsing/Shunting-yard algorithm
48 Product of divisors
48 Pseudo-random numbers/Middle-square method
48 Secure temporary file
48 Shift list elements to left by 3
48 Sorting Algorithms/Circle Sort
48 Special divisors
48 Speech synthesis
48 Subtractive generator
48 Truth table
47 10001th prime
47 Ascending primes
47 Base 16 numbers needing a to f
47 Count how many vowels and consonants occur in a string
47 Echo server
47 Factorions
47 Find prime n such that reversed n is also prime
47 Find words which contains all the vowels
47 Fivenum
47 Flipping bits game
47 Input/Output for pairs of numbers
47 Knapsack problem/Bounded
47 Lah numbers
47 Loops/Wrong ranges
47 Nice primes
47 Permutations by swapping
47 Sum to 100
47 Sutherland-Hodgman polygon clipping
47 Terminal control/Dimensions
47 Type detection
46 Abbreviations, simple
46 Atomic updates
46 Carmichael 3 strong pseudoprimes
46 Compiler/lexical analyzer
46 Extra primes
46 Find the intersection of a line with a plane
46 Keyboard input/Flush the keyboard buffer
46 Largest number divisible by its digits
46 Palindrome dates
46 Pascal's triangle/Puzzle
46 Rosetta Code/Count examples
46 Sequence: smallest number greater than previous term with exactly n divisors
46 Sort a list of object identifiers
46 Sorting algorithms/Patience sort
46 Sudan function
46 Triplet of three numbers
45 Balanced ternary
45 Cycle detection
45 Digit fifth powers
45 Display a linear combination
45 Euler's identity
45 Find prime numbers of the form n*n*n+2
45 Hickerson series of almost integers
45 Long primes
45 MD5/Implementation
45 Mersenne primes
45 Primorial numbers
45 Pythagorean quadruples
45 Ranking methods
45 Read a file character by character/UTF8
45 S-expressions
45 Safe primes and unsafe primes
45 Sailors, coconuts and a monkey problem
45 Table creation/Postal addresses
45 Terminal control/Hiding the cursor
45 Unique characters
45 Variable-length quantity
45 Yellowstone sequence
44 Arithmetic-geometric mean/Calculate Pi
44 Brace expansion
44 Cramer's rule
44 Fairshare between two and more
44 Find squares n where n+1 is prime
44 Find words whose first and last three letters are equal
44 Four is magic
44 Frobenius numbers
44 Golden ratio/Convergence
44 Input/Output for lines of text
44 Integer roots
44 Koch curve
44 Magic squares of doubly even order
44 Numerical integration/Adaptive Simpson's method
44 Percentage difference between images
44 Permutations with repetitions
44 Primes whose sum of digits is 25
44 Scope/Function names and labels
44 Sorting algorithms/Strand sort
44 Steady squares
44 Summarize and say sequence
44 Terminal control/Inverse video
44 Voronoi diagram
43 Chaocipher
43 Church numerals
43 Cousin primes
43 Eban numbers
43 Function prototype O
43 GUI enabling/disabling of controls
43 Implicit type conversion
43 Inverted index
43 Kahan summation
43 Modular arithmetic
43 Numbers with prime digits whose sum is 13
43 Penney's game
43 Prime conspiracy
43 Show the (decimal) value of a number of 1s appended with a 3, then squared
43 Sort the letters of string in alphabetical order
43 Statistics/Normal distribution
43 Test integerness
43 Topswops
43 Vampire number
42 Bitmap/Bézier curves/Cubic
42 Calendar - for "REAL" programmers O O O
42 Cheryl's birthday
42 Circular primes
42 Fibonacci word/fractal
42 Find palindromic numbers in both binary and ternary bases
42 Knuth's algorithm S
42 Multi-dimensional array
42 Multiple regression
42 Parallel calculations
42 Pathological floating point problems
42 Permutation test
42 Pythagoras tree
42 QR decomposition
42 Rosetta Code/Find bare lang tags
41 Alternade words
41 Apply a digital filter (direct form II transposed)
41 Bitwise IO
41 Create a file on magnetic tape O
41 Cuban primes
41 Dice game probabilities
41 Draw a rotating cube
41 Events
41 Find words with alternating vowels and consonants
41 LU decomposition
41 Lychrel numbers
41 Maze solving
41 Metered concurrency
41 Metronome
41 Numbers in base-16 representation that cannot be written with decimal digits
41 Numbers whose binary and ternary digit sums are prime
41 Old Russian measure of length
41 Parametric polymorphism O
41 Pinstripe/Display
41 Ray-casting algorithm
41 Solve the no connection puzzle
41 Strange unique prime triplets
41 Successive prime differences
41 Sum of elements below main diagonal of matrix
41 Xiaolin Wu's line algorithm
40 Arithmetic numbers
40 Break OO privacy O O O
40 Change e letters to i in words
40 Determine if two triangles overlap
40 Entropy/Narcissist
40 Find if a point is within a triangle
40 First 9 prime Fibonacci number
40 Length of an arc between two angles
40 Longest common suffix
40 Minimum number of cells after, before, above and below NxN squares
40 Möbius function
40 Numbers with equal rises and falls
40 Numerical integration/Gauss-Legendre Quadrature
40 Parsing/RPN to infix conversion
40 Polyspiral
40 Positive decimal integers with the digit 1 occurring exactly twice
40 Smarandache prime-digital sequence
40 Square-free integers
40 Word wheel
39 AVL tree
39 Abelian sandpile model
39 Algebraic data types O
39 Bitmap/Bézier curves/Quadratic
39 Check output device is a terminal
39 Common list elements
39 Conjugate transpose
39 Constrained genericity O O
39 Create an object at a given address O O O
39 Diversity prediction theorem
39 Find first and last set bit of a long integer
39 Find first missing positive
39 Find minimum number of coins that make a given value
39 First power of 2 that has leading decimal digits of 12
39 Jacobi symbol
39 Machine code O
39 Minesweeper game
39 Motzkin numbers
39 Mutex
39 Object serialization O O O
39 Order disjoint list items
39 Parse command-line arguments
39 Perlin noise
39 RIPEMD-160
39 RSA code
39 Set puzzle
39 Strong and weak primes
39 Terminal control/Unicode output
39 Twin primes
38 Append numbers at same position in strings
38 Calkin-Wilf sequence
38 Deceptive numbers
38 Esthetic numbers
38 Faulhaber's triangle
38 Greedy algorithm for Egyptian fractions
38 Harmonic series
38 MD4
38 Minimum multiple of m where digital sum equals m
38 Mosaic matrix
38 Multiline shebang
38 Negative base numbers
38 Numbers in base 10 that are palindromic in bases 2, 4, and 16
38 Numbers with same digit set in base 10 and base 16
38 Ordered partitions
38 Pentagram
38 Sorting algorithms/Cycle sort
38 Subset sum problem
38 Superellipse
38 Unique characters in each string
38 Zumkeller numbers
37 Angles (geometric), normalization and conversion
37 Bacon cipher
37 Doomsday rule
37 Find words which contain the most consonants
37 Gauss-Jordan matrix inversion
37 Maximum difference between adjacent elements of list
37 Minimum numbers of three lists
37 Neighbour primes
37 Peano curve
37 Pell's equation
37 Poker hand analyser
37 Product of min and max prime factors
37 Rosetta Code/Find unimplemented tasks
37 Summarize primes
37 Terminal control/Cursor movement
37 Textonyms
36 Bin given limits
36 Burrows–Wheeler transform
36 Canonicalize CIDR
36 Chemical calculator
36 Color wheel
36 Common sorted list
36 Death Star
36 Decimal floating point number to binary
36 Descending primes
36 Four sides of square
36 Galton box animation
36 Generate random numbers without repeating a value
36 Law of cosines - triples
36 Long literals, with continuations
36 Mayan numerals
36 Numbers which are the cube roots of the product of their proper divisors
36 Partition function P
36 Pragmatic directives
36 Sexy primes
36 Solve a Hidato puzzle
36 Sylvester's sequence
36 Terminal control/Preserve screen
36 URL parser
36 Weird numbers
36 Words from neighbour ones
35 Bitmap/Histogram
35 Check input device is a terminal
35 Day of the week of Christmas and New Year
35 Decision tables
35 Distinct power numbers
35 Exactly three adjacent 3 in lists
35 Faulhaber's formula
35 First perfect square in base n with n unique digits
35 Jacobsthal numbers
35 Largest prime factor
35 Memory layout of a data structure
35 Mian-Chowla sequence
35 Minimum positive multiple in base 10 using only 0 and 1
35 Odd words
35 Parameterized SQL statement
35 Partition an integer x into n primes
35 Primes with digits in nondecreasing order
35 Reflection/List properties O O
35 Resistor mesh
35 Simple database
35 Sum and product puzzle
35 Super-d numbers
35 Topic variable O O
35 Unprimeable numbers
35 Use another language to call a function
35 Wieferich primes
35 Word break problem
34 Chebyshev coefficients
34 Cullen and Woodall numbers
34 Deconvolution/1D
34 Executable library O
34 FTP
34 Monads/Maybe monad
34 Multiplicative order
34 N-smooth numbers
34 Odd squarefree semiprimes
34 Parallel brute force
34 Pierpont primes
34 Prime numbers which contain 123
34 Straddling checkerboard
34 Verify distribution uniformity/Chi-squared test
34 Video display modes O O
34 Write to Windows event log O
34 Zhang-Suen thinning algorithm
33 Bioinformatics/Sequence mutation
33 Biorhythms
33 Bitcoin/address validation
33 Checkpoint synchronization
33 Concatenate two primes is also prime
33 Execute SNUSP
33 HTTPS/Authenticated
33 Hunt the Wumpus
33 Increasing gaps between consecutive Niven numbers
33 Largest five adjacent number
33 Last list item
33 Next highest int from digits
33 Piprimes
33 Prime triplets
33 Random Latin squares
33 Range consolidation
33 Set of real numbers
33 Sierpinski arrowhead curve
33 Sierpinski pentagon
33 Sorting algorithms/Cocktail sort with shifting bounds
33 Stirling numbers of the first kind
33 Stirling numbers of the second kind
33 Sum of primes in odd positions is prime
33 Sum of square and cube digits of an integer are primes
33 Summation of primes
32 Chat server O
32 Curzon numbers
32 Duffinian numbers
32 Erdős-primes
32 Euler's constant 0.5772...
32 Finite state machine
32 First class environments
32 Generate random chess position
32 Giuga numbers
32 Go Fish
32 Idiomatically determine all the characters that can be used for symbols
32 Keyboard macros O
32 Kronecker product based fractals
32 Nonoblock
32 Numeric error propagation
32 Own digits power sum
32 Plasma effect
32 Ramsey's theorem
32 Reverse the order of lines in a text file while preserving the contents of each line
32 Rosetta Code/Fix code tags
32 Selectively replace multiple instances of a character within a string
32 State name puzzle
32 Sunflower fractal
32 Window creation/X11
31 A* search algorithm
31 Arena storage pool O
31 Changeable words
31 Check Machin-like formulas
31 Cistercian numerals
31 Compiler/virtual machine interpreter
31 Cut a rectangle
31 Honaker primes
31 Honeycombs
31 Legendre prime counting function
31 Merge and aggregate datasets
31 Monads/List monad
31 Numeric separator syntax
31 Ramer-Douglas-Peucker line simplification
31 Reflection/List methods O O
31 Sleeping Beauty problem
31 Smallest multiple
31 Snake and ladder
31 Stream merge
31 Teacup rim text
31 The ISAAC cipher
31 Tonelli-Shanks algorithm
31 Total circles area
31 Update a configuration file
30 Almkvist-Giullera formula for pi
30 Birthday problem
30 Collect and sort square numbers in ascending order from three lists
30 Consecutive primes with ascending or descending differences
30 De Bruijn sequences
30 Deming's funnel
30 Factorial primes
30 Fermat numbers
30 Find adjacent primes which differ by a square integer
30 Find largest left truncatable prime in a given base
30 Fixed length records
30 Formal power series
30 Idoneal numbers
30 Mind boggling card trick
30 Natural sorting
30 Order by pair comparisons
30 Palindromic gapful numbers
30 Palindromic primes
30 Percolation/Mean run density
30 Play recorded sounds
30 Prime words
30 Quadrat special primes
30 Same fringe
30 Special neighbor primes
30 Superpermutation minimisation
30 Table creation
29 Active Directory/Connect O
29 Audio alarm
29 Card shuffles
29 Continued fraction/Arithmetic/G(matrix ng, continued fraction n)
29 Coprime triplets
29 Decorate-sort-undecorate idiom
29 Exponentiation with infix operators in (or operating on) the base
29 Fraction reduction
29 Longest substrings without repeating characters
29 Nautical bell
29 Next special primes
29 Numbers whose count of divisors is prime
29 Orbital elements
29 Paraffins
29 Pseudo-random numbers/PCG32
29 Rare numbers
29 Safe addition
29 Sequence of primorial primes
29 Shortest common supersequence
29 Smallest power of 6 whose decimal expansion contains n
29 Solve a Holy Knight's tour
29 Spelling of ordinal numbers
29 Sum of two adjacent numbers are primes
29 Thiele's interpolation formula
29 Two's complement
29 UPC
29 Ulam numbers
29 World Cup group stage
28 Abelian sandpile model/Identity
28 Base58Check encoding
28 Brilliant numbers
28 Cipolla's algorithm
28 Cyclops numbers
28 De Polignac numbers
28 Distributed programming
28 Elliptic curve arithmetic
28 Euclid-Mullin sequence
28 Function frequency
28 Image convolution
28 Intersecting number wheels
28 K-means++ clustering
28 Magic squares of singly even order
28 Matrix chain multiplication
28 Padovan n-step number sequences
28 Padovan sequence
28 Palindromic primes in base 16
28 Permutations/Rank of a permutation
28 Permuted multiples
28 Playfair cipher
28 Primes which contain only one odd digit
28 Primes whose first and last number is 3
28 Pseudo-random numbers/Splitmix64
28 Riordan numbers
28 Self numbers
28 Snake
28 Wagstaff primes
28 Welch's t-test
28 Wilson primes of order n
28 Yahoo! search interface
27 15 puzzle solver
27 Anadromes
27 Colorful numbers
27 Commatizing numbers
27 Cubic special primes
27 EKG sequence convergence
27 Elementary cellular automaton/Random number generator
27 File size distribution
27 Getting the number of decimal places
27 Hex words
27 Klarner-Rado sequence
27 Kolakoski sequence
27 Kosaraju
27 Linux CPU utilization
27 Lucky and even lucky numbers
27 Magic constant
27 Make a backup file
27 Parse an IP Address
27 Print itself
27 RCRPG
27 Reverse the gender of a string
27 Sierpinski curve
27 Simulate input/Keyboard
26 ASCII art diagram converter
26 Assertions in design by contract
26 Determine sentence type
26 Hough transform
26 Largest difference between adjacent primes
26 List rooted trees
26 Markov chain text generator
26 Mastermind
26 Periodic table
26 Print debugging statement
26 Record sound
26 Soloway's recurring rainfall
26 Sort primes from list to a list
26 Special factorials
26 Substring primes
26 Sum data type
26 The sieve of Sundaram
26 Wordle comparison
25 Achilles numbers
25 Compiler/code generator
25 Composite numbers k with no single digit factors whose factors are all substrings of k
25 Continued fraction/Arithmetic/G(matrix ng, continued fraction n1, continued fraction n2)
25 Goldbach's comet
25 Inconsummate numbers in base 10
25 Index finite lists of positive integers
25 Joystick position
25 Largest product in a grid
25 Levenshtein distance/Alignment
25 Main step of GOST 28147-89
25 Median filter
25 Monads/Writer monad
25 Native shebang
25 Perceptron
25 Permutations with some identical elements
25 Pseudo-random numbers/Xorshift star
25 Reflection/Get source O O
25 SOAP
25 Sine wave
25 Solve a Hopido puzzle
25 Solve a Numbrix puzzle
25 Sphenic numbers
25 Variable declaration reset
25 Vibrating rectangles
25 Zeckendorf arithmetic
24 Active Directory/Search for a user O
24 Addition chains
24 Air mass
24 Bilinear interpolation
24 Blum integer
24 Compiler/syntax analyzer
24 Create an object/Native demonstration O
24 Find duplicate files
24 Matrix digital rain
24 Metallic ratios
24 Minimum primes
24 N-body problem
24 Pandigital prime
24 Prime numbers p for which the sum of primes less than or equal to p is prime
24 Round-robin tournament schedule
24 Sequence: nth number with exactly n divisors
24 Singly-linked list/Element removal
24 Sokoban
24 Solve triangle solitare puzzle
24 Untrusted environment
24 Vigenère cipher/Cryptanalysis
23 Camel case and snake case
23 Conjugate a Latin verb
23 Draw pixel 2
23 Elementary cellular automaton/Infinite length
23 Juggler sequence
23 K-d tree
23 Knuth's power tree
23 Largest palindrome product
23 Latin Squares in reduced form
23 Line circle intersection
23 Long stairs
23 Montgomery reduction
23 Names to numbers
23 Nested templated data
23 Nonogram solver
23 Numbers which are not the sum of distinct squares
23 Pancake numbers
23 Percolation/Site percolation
23 Pig the dice game/Player
23 Polynomial synthetic division
23 Practical numbers
23 Quoting constructs
23 Safe and Sophie Germain primes
23 Smallest numbers
23 Special pythagorean triplet
23 Useless instructions
23 Vogel's approximation method
22 Arithmetic derivative
22 Bitcoin/public point to address
22 Calmo numbers
22 Data Encryption Standard
22 Double Twin Primes
22 Eertree
22 Logistic curve fitting in epidemiology
22 Meissel–Mertens constant
22 Modified random distribution
22 Nimber arithmetic
22 O'Halloran numbers
22 Ormiston pairs
22 Peaceful chess queen armies
22 Percolation/Mean cluster density
22 Primes - allocate descendants to their ancestors
22 Pseudo-random numbers/Combined recursive generator MRG32k3a
22 Radical of an integer
22 Safe mode
22 Selective file copy
22 Separate the house number from the street name
22 Simulate input/Mouse
22 Tarjan
22 Two bullet roulette
22 Window management
21 Arithmetic coding/As a generalized change of radix
21 Aspect oriented programming
21 Color quantization
21 Compare sorting algorithms' performance
21 Cyclotomic polynomial
21 Fortunate numbers
21 HTTPS/Client-authenticated O
21 Iccanobif primes
21 Imaginary base numbers
21 Jaro-Winkler distance
21 Just in time processing on a character stream
21 Pseudorandom number generator image
21 Readline interface
21 Transportation problem
21 Word ladder
20 Bitmap/Read an image through a pipe
20 Compiler/AST interpreter
20 Equal prime and composite sums
20 Erdős-Nicolas numbers
20 Execute Computer/Zero O
20 Most frequent k chars distance
20 P-value correction
20 Prime triangle
20 Repunit primes
20 Ruth-Aaron numbers
20 SQL-based authentication
20 Self-hosting compiler
20 Set right-adjacent bits
20 Sierpinski square curve
20 Square root by hand
20 Sub-unit squares
20 Terminal control/Positional read O
20 Tree from nesting levels
20 Ultra useful primes
20 XML validation
19 Bifid cipher
19 Bitmap/PPM conversion through a pipe
19 Bézier curves/Intersections
19 CalmoSoft primes
19 Chernick's Carmichael numbers
19 Code segment unload O
19 Distribution of 0 digits in factorial series
19 Find URI in text
19 Forbidden numbers
19 Free polyominoes enumeration
19 Gradient descent
19 Minimal steps down to 1
19 OpenWebNet password
19 Pairs with common factors
19 Pell numbers
19 Penrose tiling
19 Penta-power prime seeds
19 Percolation/Bond percolation
19 Proof O O O
19 Retrieve and search chat history
19 Rhonda numbers
19 SEND + MORE = MONEY
19 SHA-256 Merkle tree
19 Simulated annealing
19 VList
19 Wolstenholme numbers
18 Banker's algorithm
18 Bernstein basis polynomials
18 Binary coded decimal
18 Bioinformatics/Subsequence
18 Jaccard index
18 Longest palindromic substrings
18 Minkowski question-mark function
18 Multiplicatively perfect numbers
18 NYSIIS
18 Non-transitive dice
18 Ormiston triples
18 Particle swarm optimization
18 Polynomial derivative
18 Quad-power prime seeds
18 Ramanujan's constant
18 Rendezvous
18 Sorting algorithms/Tree sort on a linked list
18 Square form factorization
18 Suffix tree
18 Three word location
18 Word search
18 XXXX redacted
17 ADFGVX cipher
17 Canny edge detector
17 Curve that touches three points
17 Earliest difference between prime gaps
17 Extreme primes
17 Four is the number of letters in the ...
17 Geohash
17 Geometric algebra
17 Gotchas
17 Home primes
17 Iterators
17 Overloaded operators
17 Pentomino tiling
17 Pisano period
17 Primes: n*2^m+1
17 Rodrigues’ rotation formula
17 Steffensen's method
17 Topological sort/Extracted top item
17 Tropical algebra overloading
17 Unit testing
17 Upside-down numbers
17 War card game
17 Zsigmondy numbers
16 Boyer-Moore string search
16 Count the coins/0-1
16 Even numbers which cannot be expressed as the sum of two twin primes
16 Faces from a mesh
16 Factorial base numbers indexing permutations of a collection
16 Find Chess960 starting position identifier
16 Functional coverage tree
16 Interactive help
16 Isograms and heterograms
16 Jordan-Pólya numbers
16 Multi-base primes
16 Railway circuit
16 Run as a daemon or service
16 Search in paragraph's text
16 Sisyphus sequence
16 Solve hanging lantern problem
16 Tetris
16 Text completion
16 Triangular numbers
16 Untouchable numbers
16 Verhoeff algorithm
15 ASCII control characters
15 Anaprimes
15 Distance and Bearing
15 Erdös-Selfridge categorization of primes
15 Graph colouring
15 Magic numbers
15 Mayan calendar
15 One-time pad
15 Rainbow
15 Ramanujan primes
15 Simple turtle graphics
15 Smarandache-Wellin primes
15 Wordiff
14 16 puzzle game
14 Audio frequency generator
14 Binomial transform
14 Centroid of a set of N-dimensional points
14 Checksumcolor
14 Colour pinstripe/Printer
14 Deconvolution/2D+
14 Display an outline as a nested table
14 Fibonacci matrix-exponentiation
14 Gaussian primes
14 Generalised floating point addition
14 Greed
14 Hourglass puzzle
14 Knuth-Morris-Pratt string search
14 Launch rocket with countdown and acceleration in stdout
14 N-grams
14 Penholodigital squares
14 Powerful numbers
14 Prime numbers whose neighboring pairs are tetraprimes
14 Set, the card game
14 Sieve of Pritchard
14 Time-based one-time password algorithm
14 Using a speech engine to highlight words
13 Bioinformatics/Global alignment
13 Boustrophedon transform
13 Catmull–Clark subdivision surface
13 Countdown
13 Execute CopyPasta Language
13 Fermat pseudoprimes
13 Inventory sequence
13 One-two primes
13 Pan base non-primes
13 Ramanujan primes/twins
13 Singular value decomposition
13 Spoof game
13 Super-Poulet numbers
13 Terminal control/Restricted width positional input/No wrapping
13 Tree datastructures
13 Walsh matrix
13 Wasteful, equidigital and frugal numbers
12 CORDIC
12 Combinations with repetitions/Square digit chain
12 Distinct palindromes within decimal numbers
12 Elliptic Curve Digital Signature Algorithm
12 External sort
12 French Republican calendar
12 Morpion solitaire
12 Peripheral drift illusion
12 Pinstripe/Printer
12 Prime reciprocal sum
12 Range modifications
12 Resistance calculator
12 Rosetta Code/Rank languages by number of users
12 Rosetta Code/Tasks without examples
12 Solve equations with substitution method
12 Starting a web browser
12 Suffixation of decimal numbers
12 Tupper's self-referential formula
11 Addition-chain exponentiation
11 Babylonian spiral
11 Brace expansion using ranges
11 Discrete Fourier transform
11 IPC via named pipe O
11 Least m such that n! + m is prime
11 N-queens minimum and knights and bishops
11 Numerical and alphabetical suffixes
11 OpenGL/Utah teapot
11 Parse EBNF
11 Sort an outline at every level
11 Statistics/Chi-squared distribution
11 Terminal control/Restricted width positional input/With wrapping
11 Transliterate English text using the Greek alphabet
11 URL shortener
11 Undulating numbers
10 Check if two polygons overlap
10 Compiler/Verifying syntax
10 Factor-perfect numbers
10 GSTrans string conversion
10 Integer long division
10 Numbers k such that the last letter of k is the same as the first letter of k+1
10 Particle fountain
10 Price list behind API
10 Raster bars
10 Resistance network calculator
10 Robots
10 Singly-linked list/Reversal
10 Smallest number k such that k+2^m is composite for all m less than k
10 Sorensen–Dice coefficient
10 Tamagotchi emulator
10 Text to HTML
10 User defined pipe and redirection operators
10 Worthwhile task shaving
9 Apéry's constant
9 B-spline
9 Black box
9 Check if a polygon overlaps with a rectangle
9 Consistent overhead byte stuffing
9 Doubly-linked list/Element removal
9 Engel expansion
9 Fibonacci heap
9 Hex dump
9 I'm a software engineer, get me out of here
9 Marching squares
9 Multidimensional Newton-Raphson method
9 OpenGL pixel shader
9 Random sentence from book
9 Rosetta Code/Run examples
9 Sealed classes and methods
9 Segmentation fault protection
9 Smallest enclosing circle problem
8 Audio overlap loop
8 Dating agency
8 Eisenstein primes
8 Hexapawn
8 Horse racing
8 Inner classes
8 JSON pointer
8 P-Adic numbers, basic
8 Recursive descent parser generator
8 Remote agent/Agent logic
8 Remote agent/Simulation
8 Rice coding
8 Simulated optics experiment/Data analysis
8 Simulated optics experiment/Simulator
8 Strassen's algorithm
8 Syntax highlighting using Mediawiki formatting
8 Waveform analysis/Doh ray me
8 WiktionaryDumps to words
7 Anagram generator
7 Autogram checker
7 Boids
7 Chess player
7 Compiler/Simple file inclusion pre processor
7 Create an executable for a program in an interpreted language
7 Cycles of a permutation
7 Dominoes
7 English cardinal anagrams
7 Exponential digital sums
7 Lagrange Interpolation
7 Latin Squares in reduced form/Randomizing using Jacobson and Matthews' technique
7 Process SMIL directives in XML data
7 Red black tree sort
7 Remote agent/Agent interface
7 Roots of a cubic polynomial
7 Selection bias in clinical sciences
7 Solve a Rubik's cube
7 Wave function collapse
6 CLI-based maze-game
6 Convert CSV records to TSV
6 Create your own text control codes
6 Divide a rectangle into a number of unequal triangles
6 OLE automation O
6 P-Adic square roots
6 Posit numbers/encoding
6 Rosetta Code/List authors of task descriptions
6 Ukkonen’s suffix tree construction
6 Use a REST API
6 Vidir
6 Visitor pattern
5 Diophantine linear system solving
5 Erdős–Woods numbers
5 Generalised floating point multiplication
5 Multiton
5 Number triplets game
5 Posit numbers/decoding
5 Sanitize user input
5 Solving coin problems
5 Szymański's algorithm
5 Unicode polynomial equation
5 Waveform analysis/Top and tail
5 Weather routing
4 15 puzzle game in 3D
4 Blackjack strategy
4 Color separation
4 Compiler/Preprocessor
4 Cross compilation
4 IRC gateway O
4 Protecting Memory Secrets
4 Uno (card game)
4 WebGL rotating F
3 3d turtle graphics
3 Elevator simulation