# Reports:Tasks not implemented in D

**Awareness**

If

**D**is a language you like, or are interested in, please inform your fellow members of the D community; this page can't be emptied without your and their participation.

## Contents

## Not implemented[edit]

These are currently not implemented in D. Please implement some if you can. If any tasks are not possible or too complex in D, they should not be on this list. To mark a task as such, add **{{omit from|D}}**, preserving the capitalization of the language, to that task. It will appear below under the "Not Considered" section.

### 2

### A

### B

### C

- Calkin-Wilf sequence
- Canonicalize CIDR
- Catmull–Clark subdivision surface
- Chaos game
- Chernick's Carmichael numbers
- Church numerals
- Color of a screen pixel
- Color wheel
- Colour bars/Display
- Colour pinstripe/Display
- Colour pinstripe/Printer
- Compare length of two strings
- Compiler/AST interpreter
- Compiler/code generator
- Compiler/lexical analyzer
- Compiler/syntax analyzer
- Compiler/virtual machine interpreter
- Consecutive primes with ascending or descending differences
- Currency

### D

### E

### F

- FASTA format
- FTP
- Faces from a mesh
- Factorial base numbers indexing permutations of a collection
- Factorions
- Fermat numbers
- File size distribution
- Find Chess960 starting position identifier
- Find duplicate files
- Find largest left truncatable prime in a given base
- Fixed length records
- Fortunate numbers
- Four is magic
- Four is the number of letters in the ...
- French Republican calendar
- Function frequency
- Functional coverage tree

### G

### I

### L

- Largest proper divisor of n
- Latin Squares in reduced form/Randomizing using Jacobson and Matthews’ Technique
- Law of cosines - triples
- Legendre prime counting function
- Long literals, with continuations
- Long primes
- Long year
- Loops/Increment loop index within loop body
- Loops/With multiple ranges
- Loops/Wrong ranges

### M

- MAC Vendor Lookup
- Magnanimous numbers
- Mastermind
- Matrix chain multiplication
- Matrix digital rain
- Mayan calendar
- Mayan numerals
- McNuggets problem
- Merge and aggregate datasets
- Mertens function
- Metallic ratios
- Metronome
- Mian-Chowla sequence
- Mind boggling card trick
- Minimal steps down to 1
- Minkowski question-mark function
- Modified random distribution
- Monads/List monad
- Monads/Maybe monad
- Monads/Writer monad
- Motzkin numbers
- Mouse position
- Musical scale

### N

### P

- P-Adic numbers, basic
- P-Adic square roots
- Padovan n-step number sequences
- Padovan sequence
- Palindrome dates
- Palindromic gapful numbers
- Parametrized SQL statement
- Parse an IP Address
- Partition function P
- Password generator
- Pathological floating point problems
- Pattern matching
- Peano curve
- Pentagram
- Pentomino tiling
- Perfect totient numbers
- Peripheral drift illusion
- Pinstripe/Display
- Pinstripe/Printer
- Pisano period
- Plasma effect
- Play recorded sounds
- Plot coordinate pairs
- Polyspiral
- Primes - allocate descendants to their ancestors
- Pseudo-random numbers/Middle-square method
- Pseudo-random numbers/Splitmix64
- Pythagoras tree

### R

- RPG attributes generator
- Ramanujan's constant
- Ramanujan primes/twins
- Random sentence from book
- Range consolidation
- Read a file character by character/UTF8
- Record sound
- Reflection/Get source
- Retrieve and search chat history
- Rosetta Code/Find bare lang tags
- Rosetta Code/Find unimplemented tasks
- Rosetta Code/Rank languages by number of users

### S

- SHA-256 Merkle tree
- SOAP
- SQL-based authentication
- Scope/Function names and labels
- Scope modifiers
- Search a list of records
- Self numbers
- Send an unknown method call
- Sequence: smallest number greater than previous term with exactly n divisors
- Sequence: smallest number with exactly n divisors
- Sequence of primorial primes
- Set right-adjacent bits
- Sexy primes
- Sierpinski arrowhead curve
- Sierpinski square curve
- Simulate input/Keyboard
- Simulate input/Mouse
- Sleeping Beauty problem
- Smarandache prime-digital sequence
- Snake
- Sort a list of object identifiers
- Sort an outline at every level
- Sort numbers lexicographically
- Sorting algorithms/Cocktail sort with shifting bounds
- Special characters
- Speech synthesis
- Spelling of ordinal numbers
- Spinning rod animation/Text
- Square form factorization
- Strassen's algorithm
- Suffixation of decimal numbers
- Sum of elements below main diagonal of matrix
- Summarize primes
- Superellipse
- Sylvester's sequence

### T

- Table creation/Postal addresses
- Tarjan
- Teacup rim text
- Terminal control/Cursor movement
- Terminal control/Dimensions
- Terminal control/Hiding the cursor
- Terminal control/Inverse video
- Terminal control/Positional read
- Terminal control/Preserve screen
- Terminal control/Unicode output
- The sieve of Sundaram
- Tree datastructures
- Tree from nesting levels
- Twin primes
- Two bullet roulette

### Draft tasks without implementation[edit]

These tasks are drafts, meaning they largely need more work to turn them into full tasks. Perhaps you can help by trying to implement them in D (after all, one of the key requirements for a task being non-draft is multiple implementations, preferably in widely different languages) but be aware that this may be difficult because of lack of definition of the task itself.

### A

### B

### C

- CLI-based maze-game
- Camel case and snake case
- Change e letters to i in words
- Changeable words
- Checksumcolor
- Chess player
- Code Golf: Code Golf
- Code segment unload
- Collect and sort square numbers in ascending order from three lists
- Common list elements
- Common sorted list
- Compiler/Simple file inclusion pre processor
- Compiler/Verifying syntax
- Composite numbers k with no single digit factors whose factors are all substrings of k
- Concatenate two primes is also prime
- Conjugate a Latin verb
- Continued fraction/Arithmetic/G(matrix ng, continued fraction n)
- Continued fraction/Arithmetic/G(matrix ng, continued fraction n1, continued fraction n2)
- Coprime triplets
- Coprimes
- Count how many vowels and consonants occur in a string
- Count the coins/0-1
- Cousin primes
- Create your own text control codes
- Cubic Special Primes
- Cullen and Woodall numbers
- Curve that touches three points
- Cyclops numbers

### D

- Dating agency
- Day of the week of Christmas and New Year
- Digit fifth powers
- Diophantine linear system solving
- Discrete Fourier transform
- Distinct Palindromes within decimal numbers
- Distinct power numbers
- Distribution of 0 Digits in factorial series
- Divide a rectangle into a number of unequal triangles
- Dominoes
- Doomsday rule
- Doubly-linked list/Element removal
- Draw pixel 2

### E

### F

- Fibonacci heap
- Fibonacci matrix-exponentiation
- Find URI in text
- Find adjacent primes which differ by a square integer
- Find first missing positive
- Find minimum number of coins that make a given value
- Find prime n such that reversed n is also prime
- Find prime numbers of the form n*n*n+2
- Find square difference
- Find squares n where n+1 is prime
- Find words which contain the most consonants
- Find words which contains all the vowels
- Find words which contains more than 3 e vowels
- Find words whose first and last three letters are equal
- Find words with alternating vowels and consonants
- First 9 Prime Fibonacci Number
- Frobenius numbers

### G

### I

### L

- Largest difference between adjacent primes
- Largest five adjacent number
- Largest palindrome product
- Largest prime factor
- Largest product in a grid
- Last list item
- Launch rocket with countdown and acceleration in stdout
- Linux CPU utilization
- Long stairs
- Longest palindromic substrings
- Longest substrings without repeating characters

### M

- Magic constant
- Make a backup file
- Maximum difference between adjacent elements of list
- Minimum multiple of m where digital sum equals m
- Minimum number of cells after, before, above and below NxN squares
- Minimum numbers of three lists
- Minimum primes
- Morpion solitaire
- Most frequent k chars distance
- Multi-base primes
- Multidimensional Newton-Raphson method
- Multiline shebang
- Multiton

### N

- Native shebang
- Neighbour primes
- Next special primes
- Number triplets game
- Numbers divisible by their individual digits, but not by the product of their digits.
- Numbers in base-16 representation that cannot be written with decimal digits
- Numbers in base 10 that are palindromic in bases 2, 4, and 16
- Numbers which are not the sum of distinct squares
- Numbers which binary and ternary digit sum are prime
- Numbers whose count of divisors is prime
- Numbers with same digit set in base 10 and base 16
- Numeric separator syntax
- Numerical integration/Adaptive Simpson's method

### O

### P

- Palindromic primes
- Palindromic primes in base 16
- Pandigital prime
- Parse EBNF
- Particle fountain
- Penrose tiling
- Perceptron
- Permutations with some identical elements
- Permuted multiples
- Piprimes
- Polynomial derivative
- Polynomial synthetic division
- Positive decimal integers with the digit 1 occurring exactly twice
- Powerful numbers
- Practical numbers
- Price list behind API
- Prime numbers p which sum of prime numbers less or equal to p is prime
- Prime numbers which contain 123
- Prime triplets
- Prime words
- Primes which contain only one odd digit
- Primes whose first and last number is 3
- Primes with digits in nondecreasing order
- Print itself
- Process SMIL directives in XML data
- Pseudorandom number generator image

### R

- Railway circuit
- Ramanujan primes
- Range modifications
- Raster bars
- Recursive descent parser generator
- Remote agent/Agent interface
- Remote agent/Agent logic
- Remote agent/Simulation
- Resistance calculator
- Resistance network calculator
- Reverse the gender of a string
- Reverse the order of lines in a text file while preserving the contents of each line
- Robots
- Rodrigues’ rotation formula
- Rosetta Code/List authors of task descriptions
- Rosetta Code/Run examples
- Round-robin tournament schedule
- Run as a daemon or service
- Ruth-Aaron numbers

### S

- Safe and Sophie Germain primes
- Safe mode
- Sanitize user input
- Segmentation fault protection
- Selective file copy
- Self-hosting compiler
- Separate the house number from the street name
- Shift list elements to left by 3
- Show the (decimal) value of a number of 1s appended with a 3, then squared
- Sierpinski curve
- Simple turtle graphics
- Simulated annealing
- Sine wave
- Singly-linked list/Element removal
- Smallest enclosing circle problem
- Smallest multiple
- Smallest number k such that k+2^m is composite for all m less than k
- Smallest numbers
- Smallest power of 6 whose decimal expansion contains n
- Smallest square that begins with n
- Solve a Rubik's Cube
- Solve equations with substitution method
- Solving coin problems
- Sort primes from list to a list
- Sort the letters of string in alphabetical order
- Sorting algorithms/Tree sort on a linked list
- Special Divisors
- Special factorials
- Special neighbor primes
- Special pythagorean triplet
- Spoof game
- Starting a web browser
- Steady Squares
- Strange numbers
- Strange plus numbers
- Strange unique prime triplets
- Substring primes
- Sum data type
- Sum of first n cubes
- Sum of primes in odd positions is prime
- Sum of square and cube digits of an integer are primes
- Sum of two adjacent numbers are primes
- Summation of primes
- Sunflower fractal

### T

- Table creation
- Tamagotchi emulator
- Terminal control/Restricted width positional input/No wrapping
- Terminal control/Restricted width positional input/With wrapping
- Tetris
- Text completion
- Text to HTML
- Three word location
- Time-based one-time password algorithm
- Topological sort/Extracted top item
- Triplet of three numbers
- Tropical algebra overloading
- Two identical strings

### U

- URL shortener
- Ulam numbers
- Ultra useful primes
- Unicode polynomial equation
- Unique characters
- Unique characters in each string
- Unit testing
- Uno (Card Game)
- Untrusted environment
- Useless instructions
- User defined pipe and redirection operators
- Using a speech engine to highlight words
- Using the Meetup.com API

### W

## Requiring Attention[edit]

### Examples[edit]

These tasks have implementations in D, but somebody, somewhere, decided that the example implementation was faulty or in some other way requiring attention. If you're familiar with the task and language, please consider reviewing/correcting the example and removing the notice.

### C

### D

### F

### M

### P

### Other pages[edit]

These are other pages related to D which require attention; with your knowledge and assistance, we can improve the quality of the site's content.

### No pages found.

## Not Considered[edit]

These tasks are not generally counted toward "unimplemented", as somebody, somewhere, decided that D was inappropriate for these tasks, or implementations of them would be unenlightening. Feel free to try your hand at them anyway.

## End of List[edit]

Again, feel free to try your hand at any of the tasks listed on this page.