# Reports:Tasks not implemented in Logo

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## Contents

## Not implemented[edit]

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

### A

- AKS test for primes
- ASCII art diagram converter
- AVL tree
- Abbreviations, automatic
- Abbreviations, easy
- Abbreviations, simple
- Abelian sandpile model
- Abelian sandpile model/Identity
- Abstract type
- Abundant, deficient and perfect number classifications
- Abundant odd numbers
- Accumulator factory
- Achilles numbers
- Active Directory/Connect
- Active Directory/Search for a user
- Active object
- Add a variable to a class instance at runtime
- Additive primes
- Address of a variable
- Algebraic data types
- Align columns
- Aliquot sequence classifications
- Almkvist-Giullera formula for pi
- Almost prime
- Amb
- Amicable pairs
- Anagrams
- Anagrams/Deranged anagrams
- Angle difference between two bearings
- Angles (geometric), normalization and conversion
- Anonymous recursion
- Anti-primes
- Append a record to the end of a text file
- Apply a digital filter (direct form II transposed)
- Approximate equality
- Arbitrary-precision integers (included)
- Archimedean spiral
- Arena storage pool
- Arithmetic-geometric mean/Calculate Pi
- Arithmetic/Complex
- Arithmetic/Rational
- Arithmetic evaluation
- Array length
- Ascending primes
- Assertions
- Associative array/Iteration
- Associative array/Merging
- Atomic updates
- Attractive numbers
- Average loop length
- Averages/Mean time of day
- Averages/Median
- Averages/Mode

### B

- Babbage problem
- Balanced brackets
- Balanced ternary
- Barnsley fern
- Base64 decode data
- Bell numbers
- Benford's law
- Bernoulli numbers
- Best shuffle
- Bin given limits
- Binary digits
- Binary strings
- Bioinformatics/Sequence mutation
- Bioinformatics/base count
- Biorhythms
- Bitcoin/address validation
- Bitcoin/public point to address
- Bitmap
- Bitmap/Bresenham's line algorithm
- Bitmap/Bézier curves/Cubic
- Bitmap/Bézier curves/Quadratic
- Bitmap/Flood fill
- Bitmap/Histogram
- Bitmap/Midpoint circle algorithm
- Bitmap/PPM conversion through a pipe
- Bitmap/Read a PPM file
- Bitmap/Read an image through a pipe
- Bitmap/Write a PPM file
- Bitwise IO
- Brace expansion
- Brazilian numbers
- Break OO privacy
- Brilliant numbers
- Brownian tree
- Bulls and cows/Player
- Burrows–Wheeler transform

### C

- CRC-32
- CSV data manipulation
- CSV to HTML translation
- CUSIP
- Calculating the value of e
- Calendar
- Calendar - for "REAL" programmers
- Calkin-Wilf sequence
- Call a foreign-language function
- Call a function
- Call a function in a shared library
- Call an object method
- Canny edge detector
- Canonicalize CIDR
- Cantor set
- Carmichael 3 strong pseudoprimes
- Cartesian product of two or more lists
- Case-sensitivity of identifiers
- Casting out nines
- Catalan numbers/Pascal's triangle
- Catamorphism
- Catmull–Clark subdivision surface
- Chaocipher
- Chat server
- Check Machin-like formulas
- Check input device is a terminal
- Check output device is a terminal
- Checkpoint synchronization
- Chernick's Carmichael numbers
- Cheryl's birthday
- Chinese remainder theorem
- Chinese zodiac
- Cholesky decomposition
- Chowla numbers
- Church numerals
- Circles of given radius through two points
- Circular primes
- Cistercian numerals
- Classes
- Closest-pair problem
- Closures/Value capture
- Color quantization
- Color wheel
- Colorful numbers
- Colour bars/Display
- Colour pinstripe/Display
- Colour pinstripe/Printer
- Combinations and permutations
- Combinations with repetitions
- Commatizing numbers
- Compare a list of strings
- Compare length of two strings
- Compare sorting algorithms' performance
- Compile-time calculation
- Compiler/AST interpreter
- Compiler/Preprocessor
- Compiler/code generator
- Compiler/lexical analyzer
- Compiler/syntax analyzer
- Compiler/virtual machine interpreter
- Composite numbers k with no single digit factors whose factors are all substrings of k
- Concurrent computing
- Conjugate transpose
- Consecutive primes with ascending or descending differences
- Constrained genericity
- Constrained random points on a circle
- Continued fraction
- Continued fraction/Arithmetic/Construct from rational number
- Convert decimal number to rational
- Convert seconds to compound duration
- Convex hull
- Conway's Game of Life
- Copy stdin to stdout
- Count in factors
- Count occurrences of a substring
- Count the coins
- Cramer's rule
- Create a file
- Create a file on magnetic tape
- Create an HTML table
- Create an object at a given address
- Cuban primes
- Cullen and Woodall numbers
- Cumulative standard deviation
- Currency
- Currying
- Curzon numbers
- Cut a rectangle
- Cyclops numbers
- Cyclotomic polynomial

### D

- DNS query
- Damm algorithm
- Date manipulation
- De Bruijn sequences
- Death Star
- Deceptive numbers
- Deconvolution/1D
- Deconvolution/2D+
- Deepcopy
- Define a primitive data type
- Delegates
- Deming's Funnel
- Department numbers
- Descending primes
- Detect division by zero
- Determinant and permanent
- Determine if a string has all the same characters
- Determine if a string has all unique characters
- Determine if a string is collapsible
- Determine if a string is squeezable
- Determine if only one instance is running
- Determine if two triangles overlap
- Determine sentence type
- Dice game probabilities
- Digital root
- Digital root/Multiplicative digital root
- Dijkstra's algorithm
- Dinesman's multiple-dwelling problem
- Dining philosophers
- Disarium numbers
- Discordian date
- Display a linear combination
- Display an outline as a nested table
- Distributed programming
- Diversity prediction theorem
- Documentation
- Doubly-linked list/Definition
- Doubly-linked list/Element definition
- Doubly-linked list/Element insertion
- Doubly-linked list/Traversal
- Draw a clock
- Draw a pixel
- Draw a rotating cube
- Duffinian numbers

### E

- EKG sequence convergence
- Earliest difference between prime gaps
- Eban numbers
- Echo server
- Eertree
- Egyptian division
- Egyptian fractions
- Element-wise operations
- Elementary cellular automaton
- Elementary cellular automaton/Infinite length
- Elementary cellular automaton/Random Number Generator
- Elliptic Curve Digital Signature Algorithm
- Elliptic curve arithmetic
- Emirp primes
- Empty directory
- Empty string
- Enforced immutability
- Entropy
- Entropy/Narcissist
- Enumerations
- Environment variables
- Equal prime and composite sums
- Erdös-Selfridge categorization of primes
- Esthetic numbers
- Euler's constant 0.5772...
- Euler's identity
- Euler's sum of powers conjecture
- Euler method
- Events
- Exceptions/Catch an exception thrown in a nested call
- Executable library
- Execute Brain****
- Execute HQ9+
- Execute SNUSP
- Execute a Markov algorithm
- Exponentiation order
- Exponentiation with infix operators in (or operating on) the base
- Extend your language
- Extensible prime generator
- Extreme floating point values

### F

- FASTA format
- FTP
- Faces from a mesh
- Factorial base numbers indexing permutations of a collection
- Factorions
- Factors of a Mersenne number
- Fairshare between two and more
- Farey sequence
- Fast Fourier transform
- Faulhaber's formula
- Faulhaber's triangle
- Feigenbaum constant calculation
- Fermat numbers
- Fibonacci n-step number sequences
- Fibonacci word
- File extension is in extensions list
- File modification time
- File size
- File size distribution
- Find Chess960 starting position identifier
- Find common directory path
- Find duplicate files
- Find if a point is within a triangle
- Find largest left truncatable prime in a given base
- Find palindromic numbers in both binary and ternary bases
- Find the intersection of a line with a plane
- Find the intersection of two lines
- Find the last Sunday of each month
- Find the missing permutation
- First-class functions
- First-class functions/Use numbers analogously
- First class environments
- First perfect square in base n with n unique digits
- First power of 2 that has leading decimal digits of 12
- Five weekends
- Fivenum
- Fixed length records
- Flipping bits game
- Flow-control structures
- Floyd's triangle
- Floyd-Warshall algorithm
- Forest fire
- Fork
- Formal power series
- Fortunate numbers
- Four bit adder
- Four is magic
- Four is the number of letters in the ...
- Fraction reduction
- Fractran
- French Republican calendar
- Function composition
- Function frequency
- Function prototype
- Functional coverage tree
- Fusc sequence

### G

- GUI/Maximum window dimensions
- GUI component interaction
- GUI enabling/disabling of controls
- Galton box animation
- Gamma function
- Gauss-Jordan matrix inversion
- Gaussian elimination
- General FizzBuzz
- Generate Chess960 starting position
- Generate random chess position
- Generator/Exponential
- Get system command output
- Globally replace text in several files
- Go Fish
- Goldbach's comet
- Graph colouring
- Grayscale image
- Greatest subsequential sum
- Greyscale bars/Display
- Guess the number
- Guess the number/With feedback (player)

### H

- HTTP
- HTTPS
- HTTPS/Authenticated
- HTTPS/Client-authenticated
- Halt and catch fire
- Handle a signal
- Harmonic series
- Harshad or Niven series
- Hash from two arrays
- Hash join
- Haversine formula
- Hello world/Line printer
- Hello world/Newbie
- Hello world/Newline omission
- Hello world/Standard error
- Hello world/Web server
- Here document
- Heronian triangles
- Hickerson series of almost integers
- Hilbert curve
- History variables
- Hofstadter-Conway $10,000 sequence
- Hofstadter Figure-Figure sequences
- Hofstadter Q sequence
- Holidays related to Easter
- Home primes
- Honeycombs
- Host introspection
- Hostname
- Hough transform
- Huffman coding
- Humble numbers
- Hunt the Wumpus

### I

- IBAN
- ISBN13 check digit
- I before E except after C
- Identity matrix
- Idiomatically determine all the characters that can be used for symbols
- Idiomatically determine all the lowercase and uppercase letters
- Image convolution
- Image noise
- Imaginary base numbers
- Include a file
- Increasing gaps between consecutive Niven numbers
- Index finite lists of positive integers
- Infinity
- Inheritance/Multiple
- Inheritance/Single
- Integer overflow
- Integer sequence
- Intersecting number wheels
- Inverted index
- Inverted syntax
- Isqrt (integer square root) of X
- Iterated digits squaring

### J

### K

- K-d tree
- K-means++ clustering
- Kaprekar numbers
- Kernighans large earthquake problem
- Keyboard input/Flush the keyboard buffer
- Keyboard macros
- Knapsack problem/0-1
- Knapsack problem/Bounded
- Knapsack problem/Continuous
- Knapsack problem/Unbounded
- Knight's tour
- Knuth's algorithm S
- Knuth's power tree
- Kolakoski sequence
- Kosaraju
- Kronecker product
- Kronecker product based fractals

### L

- LU decomposition
- LZW compression
- Lah numbers
- Largest int from concatenated ints
- Largest number divisible by its digits
- Largest proper divisor of n
- Last letter-first letter
- Latin Squares in reduced form
- Latin Squares in reduced form/Randomizing using Jacobson and Matthews’ Technique
- Law of cosines - triples
- Left factorials
- Legendre prime counting function
- Leonardo numbers
- Letter frequency
- Levenshtein distance
- Levenshtein distance/Alignment
- List comprehensions
- List rooted trees
- Literals/Floating point
- Long literals, with continuations
- Long multiplication
- Long primes
- Longest common substring
- Longest increasing subsequence
- Longest string challenge
- Loops/Break
- Loops/Continue
- Loops/Increment loop index within loop body
- Loops/With multiple ranges
- Loops/Wrong ranges
- Lucas-Lehmer test
- Lucky and even lucky numbers
- Ludic numbers
- Lychrel numbers

### M

- MAC Vendor Lookup
- MD4
- MD5
- MD5/Implementation
- Machine code
- Mad Libs
- Magic 8-ball
- Magic constant
- Magic squares of doubly even order
- Magic squares of odd order
- Magic squares of singly even order
- Magnanimous numbers
- Main step of GOST 28147-89
- Make directory path
- Man or boy test
- Mastermind
- Matrix-exponentiation operator
- Matrix chain multiplication
- Matrix digital rain
- Matrix transposition
- Maximum triangle path sum
- Mayan calendar
- Mayan numerals
- Maze generation
- Maze solving
- McNuggets problem
- Median filter
- Memory allocation
- Memory layout of a data structure
- Merge and aggregate datasets
- Mertens function
- Metallic ratios
- Metaprogramming
- Metered concurrency
- Metronome
- Mian-Chowla sequence
- Miller–Rabin primality test
- Mind boggling card trick
- Minesweeper game
- Minimal steps down to 1
- Minimum multiple of m where digital sum equals m
- Minimum positive multiple in base 10 using only 0 and 1
- Minkowski question-mark function
- Modified random distribution
- Modular arithmetic
- Modular exponentiation
- Modular inverse
- Monads/List monad
- Monads/Maybe monad
- Monads/Writer monad
- Monty Hall problem
- Morse code
- Motzkin numbers
- Move-to-front algorithm
- Multi-base primes
- Multi-dimensional array
- Multifactorial
- Multiple distinct objects
- Multiple regression
- Multiplicative order
- Multisplit
- Munchausen numbers
- Munching squares
- Musical scale
- Mutex
- Möbius function

### N

- N'th
- N-smooth numbers
- Named parameters
- Naming conventions
- Narcissist
- Narcissistic decimal number
- Natural sorting
- Nautical bell
- Negative base numbers
- Nested function
- Nested templated data
- Next highest int from digits
- Nim game
- Non-continuous subsequences
- Non-decimal radices/Convert
- Non-decimal radices/Input
- Non-decimal radices/Output
- Non-transitive dice
- Nonoblock
- Nonogram solver
- Number reversal game
- Numbers which are not the sum of distinct squares
- Numbers with equal rises and falls
- Numeric error propagation
- Numerical and alphabetical suffixes
- Numerical integration/Gauss-Legendre Quadrature

### O

### P

- P-Adic numbers, basic
- P-Adic square roots
- P-value correction
- Padovan n-step number sequences
- Padovan sequence
- Palindrome dates
- Palindromic gapful numbers
- Pancake numbers
- Paraffins
- Parallel brute force
- Parallel calculations
- Parameterized SQL statement
- Parametric polymorphism
- Parse an IP Address
- Parsing/RPN calculator algorithm
- Parsing/RPN to infix conversion
- Parsing/Shunting-yard algorithm
- Partial function application
- Particle fountain
- Partition an integer x into n primes
- Partition function P
- Pascal's triangle/Puzzle
- Pascal matrix generation
- Password generator
- Pathological floating point problems
- Peaceful chess queen armies
- Peano curve
- Pell's equation
- Pell numbers
- Penney's game
- Pentagram
- Pentomino tiling
- Percentage difference between images
- Percolation/Bond percolation
- Percolation/Mean cluster density
- Percolation/Mean run density
- Percolation/Site percolation
- Perfect shuffle
- Perfect totient numbers
- Peripheral drift illusion
- Perlin noise
- Permutation test
- Permutations
- Permutations/Derangements
- Permutations/Rank of a permutation
- Permutations by swapping
- Pernicious numbers
- Phrase reversals
- Pi
- Pierpont primes
- Pig the dice game
- Pig the dice game/Player
- Pinstripe/Display
- Pinstripe/Printer
- Pisano period
- Plasma effect
- Play recorded sounds
- Playfair cipher
- Plot coordinate pairs
- Pointers and references
- Poker hand analyser
- Polymorphic copy
- Polymorphism
- Polynomial long division
- Polynomial regression
- Polyspiral
- Population count
- Pragmatic directives
- Price fraction
- Primality by Wilson's theorem
- Prime conspiracy
- Prime triangle
- Primes - allocate descendants to their ancestors
- Primorial numbers
- Priority queue
- Probabilistic choice
- Problem of Apollonius
- Program name
- Proper divisors
- Pseudo-random numbers/Combined recursive generator MRG32k3a
- Pseudo-random numbers/Middle-square method
- Pseudo-random numbers/PCG32
- Pseudo-random numbers/Splitmix64
- Pseudo-random numbers/Xorshift star
- Pythagoras tree
- Pythagorean quadruples
- Pythagorean triples

### R

- RCRPG
- RIPEMD-160
- RPG attributes generator
- RSA code
- Ramanujan's constant
- Ramanujan primes/twins
- Ramer-Douglas-Peucker line simplification
- Random Latin squares
- Random number generator (device)
- Random number generator (included)
- Random sentence from book
- Range consolidation
- Range expansion
- Range extraction
- Ranking methods
- Rare numbers
- Rate counter
- Ray-casting algorithm
- Read a configuration file
- Read a file character by character/UTF8
- Read a specific line from a file
- Read entire file
- Recaman's sequence
- Record sound
- Reduced row echelon form
- Reflection/Get source
- Reflection/List methods
- Reflection/List properties
- Regular expressions
- Remove lines from a file
- Rename a file
- Rendezvous
- Rep-string
- Repeat
- Repunit primes
- Resistor mesh
- Respond to an unknown method call
- Retrieve and search chat history
- Return multiple values
- Rhonda numbers
- Rock-paper-scissors
- Roots of a function
- Roots of unity
- Rosetta Code/Count examples
- Rosetta Code/Find bare lang tags
- Rosetta Code/Find unimplemented tasks
- Rosetta Code/Fix code tags
- Rosetta Code/Rank languages by number of users
- Rosetta Code/Rank languages by popularity
- Runge-Kutta method
- Runtime evaluation
- Runtime evaluation/In an environment
- Ruth-Aaron numbers

### S

- S-expressions
- SEDOLs
- SHA-1
- SHA-256
- SHA-256 Merkle tree
- SOAP
- SQL-based authentication
- Safe addition
- Safe primes and unsafe primes
- Sailors, coconuts and a monkey problem
- Same fringe
- Scope/Function names and labels
- Search a list of records
- Search in paragraph's text
- Secure temporary file
- Self numbers
- Semiprime
- Semordnilap
- Send an unknown method call
- Send email
- Sequence: nth number with exactly n divisors
- Sequence: smallest number greater than previous term with exactly n divisors
- Sequence: smallest number with exactly n divisors
- Sequence of primes by trial division
- Sequence of primorial primes
- Set
- Set consolidation
- Set of real numbers
- Set puzzle
- Set right-adjacent bits
- Seven-sided dice from five-sided dice
- Sexy primes
- Shell one-liner
- Shoelace formula for polygonal area
- Shortest common supersequence
- Show ASCII table
- Show the epoch
- Sierpinski arrowhead curve
- Sierpinski carpet
- Sierpinski pentagon
- Sierpinski square curve
- Simple database
- Simulate input/Keyboard
- Simulate input/Mouse
- Singleton
- Sleeping Beauty problem
- Smallest number k such that k+2^m is composite for all m less than k
- Smarandache prime-digital sequence
- Smith numbers
- Snake
- Sockets
- Sokoban
- Solve a Hidato puzzle
- Solve a Holy Knight's tour
- Solve a Hopido puzzle
- Solve a Numbrix puzzle
- Solve hanging lantern problem
- Solve the no connection puzzle
- Sort a list of object identifiers
- Sort an array of composite structures
- Sort an integer array
- Sort an outline at every level
- Sort disjoint sublist
- Sort numbers lexicographically
- Sort stability
- Sort three variables
- Sort using a custom comparator
- Sorting Algorithms/Circle Sort
- Sorting algorithms/Bead sort
- Sorting algorithms/Bogosort
- Sorting algorithms/Bubble sort
- Sorting algorithms/Cocktail sort
- Sorting algorithms/Cocktail sort with shifting bounds
- Sorting algorithms/Comb sort
- Sorting algorithms/Counting sort
- Sorting algorithms/Gnome sort
- Sorting algorithms/Heapsort
- Sorting algorithms/Insertion sort
- Sorting algorithms/Pancake sort
- Sorting algorithms/Patience sort
- Sorting algorithms/Permutation sort
- Sorting algorithms/Radix sort
- Sorting algorithms/Selection sort
- Sorting algorithms/Shell sort
- Sorting algorithms/Sleep sort
- Sorting algorithms/Stooge sort
- Sorting algorithms/Strand sort
- Soundex
- Sparkline in unicode
- Special characters
- Special variables
- Speech synthesis
- Spelling of ordinal numbers
- Spinning rod animation/Text
- Spiral matrix
- Split a character string based on change of character
- Square-free integers
- Square but not cube
- Square form factorization
- Stable marriage problem
- Stack traces
- Start from a main routine
- State name puzzle
- Statistics/Basic
- Statistics/Normal distribution
- Stem-and-leaf plot
- Stern-Brocot sequence
- Stirling numbers of the first kind
- Stirling numbers of the second kind
- Straddling checkerboard
- Strassen's algorithm
- Stream merge
- String append
- String comparison
- String interpolation (included)
- String prepend
- Strip block comments
- Strip comments from a string
- Strip control codes and extended characters from a string
- Strip whitespace from a string/Top and tail
- Strong and weak primes
- Substitution cipher
- Subtractive generator
- Successive prime differences
- Sudoku
- Suffixation of decimal numbers
- Sum and product puzzle
- Sum multiples of 3 and 5
- Sum of elements below main diagonal of matrix
- Sum to 100
- Summarize and say sequence
- Summarize primes
- Super-d numbers
- Superellipse
- Superpermutation minimisation
- Sutherland-Hodgman polygon clipping
- Sylvester's sequence
- Synchronous concurrency

### T

- Table creation/Postal addresses
- Take notes on the command line
- Tarjan
- Tau function
- Tau number
- Taxicab numbers
- Teacup rim text
- Temperature conversion
- Terminal control/Coloured text
- Terminal control/Cursor movement
- Terminal control/Dimensions
- Terminal control/Display an extended character
- Terminal control/Hiding the cursor
- Terminal control/Inverse video
- Terminal control/Positional read
- Terminal control/Preserve screen
- Terminal control/Unicode output
- Ternary logic
- Test a function
- Test integerness
- Text processing/1
- Text processing/2
- Text processing/Max licenses in use
- Textonyms
- The ISAAC Cipher
- The Name Game
- The sieve of Sundaram
- Thiele's interpolation formula
- Thue-Morse
- Tic-tac-toe
- Tokenize a string with escaping
- Tonelli-Shanks algorithm
- Top rank per group
- Topic variable
- Topological sort
- Topswops
- Total circles area
- Totient function
- Trabb Pardo–Knuth algorithm
- Tree datastructures
- Tree from nesting levels
- Truncatable primes
- Truncate a file
- Truth table
- Twelve statements
- Twin primes
- Two bullet roulette

### U

- UPC
- URL decoding
- URL encoding
- URL parser
- UTF-8 encode and decode
- Ukkonen’s suffix tree construction
- Ulam spiral (for primes)
- Ultra useful primes
- Unbias a random generator
- Unicode strings
- Unicode variable names
- Universal Turing machine
- Unix/ls
- Unprimeable numbers
- Untouchable numbers
- Update a configuration file
- Use another language to call a function
- User input/Graphical

### V

- Validate International Securities Identification Number
- Vampire number
- Van Eck sequence
- Van der Corput sequence
- Variable-length quantity
- Variable declaration reset
- Variable size/Get
- Variable size/Set
- Vector
- Vector products
- Verhoeff algorithm
- Verify distribution uniformity/Chi-squared test
- Verify distribution uniformity/Naive
- Video display modes
- Vigenère cipher
- Vigenère cipher/Cryptanalysis
- Visualize a tree
- Vogel's approximation method
- Voronoi diagram

### W

- Walk a directory/Non-recursively
- Walk a directory/Recursively
- War card game
- Water collected between towers
- Web scraping
- Weird numbers
- Wieferich primes
- Wilson primes of order n
- Window creation
- Window creation/X11
- Window management
- Word frequency
- Word ladder
- Word search
- Word wheel
- Word wrap
- Wordiff
- World Cup group stage
- Write entire file
- Write float arrays to a text file
- Write language name in 3D ASCII
- Write to Windows event log

### 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 Logo (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

- A* search algorithm
- ABC words
- ADFGVX cipher
- Addition-chain exponentiation
- Addition chains
- Air mass
- Alternade words
- Append numbers at same position in strings
- Arithmetic coding/As a generalized change of radix
- Aspect oriented programming
- Assertions in design by contract
- Audio alarm
- Audio frequency generator
- Audio overlap loop

### B

### C

- CLI-based maze-game
- Camel case and snake case
- Card shuffles
- Change e letters to i in words
- Changeable words
- Chebyshev coefficients
- Checksumcolor
- Chemical calculator
- Chess player
- Cipolla's algorithm
- Code Golf: Code Golf
- Code segment unload
- Collect and sort square numbers in ascending order from three lists
- Combinations with repetitions/Square digit chain
- Common list elements
- Common sorted list
- Compiler/Simple file inclusion pre processor
- Compiler/Verifying syntax
- 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 an object/Native demonstration
- Create your own text control codes
- Cubic special primes
- Curve that touches three points
- Cycle detection
- Cycles of a permutation

### D

- Data Encryption Standard
- Dating agency
- Day of the week of Christmas and New Year
- Days between dates
- Decimal floating point number to binary
- Decision tables
- 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 and last set bit of a long 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
- Finite state machine
- First 9 prime Fibonacci number
- Four sides of square
- Free polyominoes enumeration
- 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
- Length of an arc between two angles
- Line circle intersection
- Linux CPU utilization
- Logistic curve fitting in epidemiology
- Long stairs
- Longest common prefix
- Longest common suffix
- Longest palindromic substrings
- Longest substrings without repeating characters

### M

- Make a backup file
- Markov chain text generator
- Matrix with two diagonals
- Maximum difference between adjacent elements of list
- Mersenne primes
- Minimum number of cells after, before, above and below NxN squares
- Minimum numbers of three lists
- Minimum primes
- Modulinos
- Montgomery reduction
- Morpion solitaire
- Mosaic matrix
- Most frequent k chars distance
- Multidimensional Newton-Raphson method
- Multiline shebang
- Multiton

### N

- N-body problem
- N-queens minimum and knights and bishops
- NYSIIS
- Names to numbers
- Native shebang
- Neighbour primes
- Next special primes
- Nice primes
- Nimber arithmetic
- 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 binary and ternary digit sum are prime
- Numbers whose count of divisors is prime
- Numbers with prime digits whose sum is 13
- 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
- Parse command-line arguments
- Particle swarm optimization
- Penrose tiling
- Perceptron
- Permutations with repetitions
- 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 for which the sum of primes less than 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 whose sum of digits is 25
- Primes with digits in nondecreasing order
- Print debugging statement
- Print itself
- Process SMIL directives in XML data
- Product of divisors
- Proof
- Pseudorandom number generator image

### R

- Railway circuit
- Ramanujan primes
- Ramsey's theorem
- Range modifications
- Raster bars
- Readline interface
- Recursive descent parser generator
- Remote agent/Agent interface
- Remote agent/Agent logic
- Remote agent/Simulation
- Remove vowels from a string
- 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
- Rosetta Code/Tasks without examples
- Round-robin tournament schedule
- Run as a daemon or service

### S

- Safe and Sophie Germain primes
- Safe mode
- Sanitize user input
- Sattolo cycle
- 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
- Simulated annealing
- Sine wave
- Singly-linked list/Element removal
- Smallest enclosing circle problem
- Smallest multiple
- Smallest numbers
- Smallest power of 6 whose decimal expansion contains n
- Smallest square that begins with n
- Snake and Ladder
- Solve a Rubik's Cube
- Solve equations with substitution method
- Solve triangle solitare puzzle
- Solving coin problems
- Sort primes from list to a list
- Sort the letters of string in alphabetical order
- Sorting algorithms/Cycle sort
- Sorting algorithms/Tree sort on a linked list
- Special divisors
- Special factorials
- Special neighbor primes
- Special pythagorean triplet
- Spoof game
- Square root by hand
- Starting a web browser
- Steady squares
- Strange numbers
- Strange plus numbers
- Strange unique prime triplets
- Subset sum problem
- Substring primes
- Suffix tree
- Sum data type
- Sum of divisors
- 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 the digits of n is substring of n
- 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 between
- Text completion
- Text to HTML
- Three word location
- Time-based one-time password algorithm
- Topological sort/Extracted top item
- Transportation problem
- Triplet of three numbers
- Tropical algebra overloading
- Two identical strings
- Two sum
- Type detection

### U

### W

## Requiring Attention[edit]

### Examples[edit]

These tasks have implementations in Logo, 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.

### M

### Other pages[edit]

These are other pages related to Logo 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 Logo was inappropriate for these tasks, or implementations of them would be unenlightening. Feel free to try your hand at them anyway.

### No pages found.

## End of List[edit]

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