Erlang

Erlang is a programming language which has many features more commonly associated with an operating system than with a programming language:

• concurrent processes
• scheduling
• memory management
• distribution
• networking
• …

Tasks

• 100 doors
• 24 game
• 9 billion names of God the integer
• A+B
• ABC Problem
• AKS test for primes
• Abbreviations, automatic
• Abundant, deficient and perfect number classifications
• Accumulator factory
• Ackermann function
• Active Directory/Connect
• Active object
• Align columns
• Almost prime
• Amicable pairs
• Anagrams
• Anagrams/Deranged anagrams
• Anonymous recursion
• Anti-primes
• Apply a callback to an array
• Arbitrary-precision integers (included)
• Arena storage pool
• Arithmetic-geometric mean
• Arithmetic-geometric mean/Calculate Pi
• Arithmetic/Complex
• Arithmetic/Integer
• Array concatenation
• Array length
• Arrays
• Assertions
• Associative array/Creation
• Associative array/Iteration
• Atomic updates
• Averages/Arithmetic mean
• Averages/Mean angle
• Averages/Mean time of day
• Averages/Median
• Averages/Mode
• Averages/Pythagorean means
• Averages/Root mean square
• Averages/Simple moving average
• Babbage problem
• Balanced brackets
• Balanced ternary
• Base64 encode data
• Benford's law
• Best shuffle
• Binary digits
• Binary search
• Binary strings
• Bitcoin/address validation
• Bitmap
• Bitmap/Read a PPM file
• Bitmap/Write a PPM file
• Bitwise IO
• Bitwise operations
• Boolean values
• Bresenham's Line Algorithm
• Bulls and cows
• CRC-32
• CSV data manipulation
• CSV to HTML translation
• Caesar cipher
• Call a function
• Case-sensitivity of identifiers
• Catalan numbers
• Catalan numbers/Pascal's triangle
• Catamorphism
• Character codes
• Chat server
• Check that file exists
• Checkpoint synchronization
• Chinese remainder theorem
• Closures/Value capture
• Combinations
• Combinations and permutations
• Combinations with repetitions
• Comma quibbling
• Command-line arguments
• Comments
• Compare a list of strings
• Compare sorting algorithms' performance
• Compile-time calculation
• Compound data type
• Concurrent computing
• Conditional structures
• Continued fraction
• Convert seconds to compound duration
• Copy a string
• Count in octal
• Count occurrences of a substring
• Count the coins
• Create a file
• Create a two-dimensional array at runtime
• Create an HTML table
• Cumulative standard deviation
• Currying
• DNS query
• Date format
• Date manipulation
• Day of the week
• Days between dates
• Deepcopy
• Delete a file
• Detect division by zero
• Determine if a string is numeric
• Determine if only one instance is running
• Digital root
• Dijkstra's algorithm
• Dinesman's multiple-dwelling problem
• Dining philosophers
• Distributed programming
• Documentation
• Dot product
• Doubly-linked list/Definition
• Doubly-linked list/Element definition
• Doubly-linked list/Element insertion
• Doubly-linked list/Traversal
• Dutch national flag problem
• Dynamic variable names
• Echo server
• Egyptian division
• Egyptian fractions
• Empty directory
• Empty program
• Empty string
• Enforced immutability
• Entropy
• Entropy/Narcissist
• Enumerations
• Environment variables
• Ethiopian multiplication
• Euler method
• Evaluate binomial coefficients
• Even or odd
• Events
• Evolutionary algorithm
• Exceptions
• Exceptions/Catch an exception thrown in a nested call
• Execute Brainfuck
• Execute HQ9+
• Execute a system command
• Exponentiation operator
• Factorial
• Factors of a Mersenne number
• Factors of an integer
• Fibonacci n-step number sequences
• Fibonacci sequence
• Filter
• Find common directory path
• Find limit of recursion
• Find the last Sunday of each month
• Find the missing permutation
• First class environments
• First-class functions
• First-class functions/Use numbers analogously
• Five weekends
• FizzBuzz
• Flatten a list
• Flow-control structures
• Floyd's triangle
• Forest fire
• Fork
• Formatted numeric output
• Forward difference
• Four bit adder
• Fractran
• Function composition
• Function definition
• Function frequency
• General FizzBuzz
• Generate lower case ASCII alphabet
• Generator/Exponential
• Generic swap
• Globally replace text in several files
• Go Fish
• Gray code
• Grayscale image
• Greatest common divisor
• Greatest element of a list
• Guess the number
• Guess the number/With feedback
• Guess the number/With feedback (player)
• HTTP
• HTTPS
• Hailstone sequence
• Happy numbers
• Harshad or Niven series
• Hash from two arrays
• Hash join
• Haversine formula
• Hello world!
• Hello world/Newbie
• Hello world/Newline omission
• Hello world/Standard error
• Hello world/Text
• Hello world/Web server
• Here document
• Higher-order functions
• History variables
• Hofstadter Q sequence
• Hofstadter-Conway $10,000 sequence
• Holidays related to Easter
• Horner's rule for polynomial evaluation
• Host introspection
• Hostname
• Huffman coding
• I before E except after C
• Identity matrix
• Include a file
• Increment a numerical string
• Infinity
• Input loop
• Integer comparison
• Integer sequence
• Interactive programming
• Introspection
• Inverted index
• JSON
• Jensen's Device
• Josephus problem
• Jump anywhere
• Kaprekar numbers
• Knapsack problem/0-1
• Knapsack problem/Continuous
• Knight's tour
• Knuth shuffle
• LZW compression
• Langton's ant
• Largest int from concatenated ints
• Last Friday of each month
• Last letter-first letter
• Leap year
• Least common multiple
• Letter frequency
• Levenshtein distance
• Linear congruential generator
• List comprehensions
• Literals/Floating point
• Literals/Integer
• Literals/String
• Logical operations
• Longest common prefix
• Longest common subsequence
• Longest increasing subsequence
• Look-and-say sequence
• Loop over multiple arrays simultaneously
• Loops/Break
• Loops/Continue
• Loops/Do-while
• Loops/Downward for
• Loops/For
• Loops/For with a specified step
• Loops/Foreach
• Loops/Infinite
• Loops/N plus one half
• Loops/Nested
• Loops/While
• Lucas-Lehmer test
• Luhn test of credit card numbers
• MD4
• MD5
• Mad Libs
• Man or boy test
• Mandelbrot set
• Map range
• Matrix multiplication
• Matrix transposition
• Maze generation
• Maze solving
• Memory allocation
• Metaprogramming
• Metered concurrency
• Middle three digits
• Miller–Rabin primality test
• Modulinos
• Monte Carlo methods
• Monty Hall problem
• Multifactorial
• Multiline shebang
• Multiple distinct objects
• Multiplication tables
• Multisplit
• Mutual recursion
• N-queens problem
• Named parameters
• Non-decimal radices/Convert
• Non-decimal radices/Input
• Non-decimal radices/Output
• Nth root
• Null object
• Number names
• Number reversal game
• Object serialization
• Odd word problem
• One of n lines in a file
• One-dimensional cellular automata
• Operator precedence
• Optional parameters
• Order two numerical lists
• Ordered words
• Palindrome detection
• Pangram checker
• Parallel calculations
• Parsing/RPN calculator algorithm
• Pascal's triangle
• Pattern matching
• Perfect numbers
• Permutations
• Permutations with repetitions
• Pi
• Pick random element
• Pig the dice game
• Pig the dice game/Player
• Playing cards
• Plot coordinate pairs
• Population count
• Power set
• Pragmatic directives
• Price fraction
• Primality by trial division
• Prime decomposition
• Priority queue
• Probabilistic choice
• Program name
• Program termination
• Pythagorean triples
• Queue/Definition
• Queue/Usage
• Quickselect algorithm
• Quine
• RCRPG
• Ramsey's theorem
• Random number generator (included)
• Random numbers
• Range expansion
• Range extraction
• Rate counter
• Read a configuration file
• Read a file line by line
• Read a specific line from a file
• Read entire file
• Real constants and functions
• Regular expressions
• Remove duplicate elements
• Remove lines from a file
• Rename a file
• Rendezvous
• Repeat a string
• Return multiple values
• Reverse a string
• Rock-paper-scissors
• Roman numerals/Decode
• Roman numerals/Encode
• Roots of a function
• Rosetta Code/Count examples
• Rosetta Code/Find bare lang tags
• Rosetta Code/Find unimplemented tasks
• Rosetta Code/Fix code tags
• Rot-13
• Run-length encoding
• Runtime evaluation
• Runtime evaluation/In an environment
• SHA-1
• SHA-256
• Scope modifiers
• Scope/Function names and labels
• Search a list
• Self-describing numbers
• Semiprime
• Semordnilap
• Sequence of non-squares
• Set
• Set puzzle
• Seven-sided dice from five-sided dice
• Shell one-liner
• Short-circuit evaluation
• Show the epoch
• Sierpinski carpet
• Sierpinski triangle
• Sierpinski triangle/Graphical
• Sieve of Eratosthenes
• Simple database
• Singleton
• Singly-linked list/Element definition
• Singly-linked list/Element insertion
• Singly-linked list/Traversal
• Sleep
• Sockets
• Solve a Hidato puzzle
• Sort an array of composite structures
• Sort an integer array
• Sort disjoint sublist
• Sort stability
• Sort using a custom comparator
• Sorting algorithms/Bead sort
• Sorting algorithms/Bubble sort
• Sorting algorithms/Gnome sort
• Sorting algorithms/Insertion sort
• Sorting algorithms/Merge sort
• Sorting algorithms/Quicksort
• Sorting algorithms/Selection sort
• Sorting algorithms/Sleep sort
• Soundex
• Special characters
• Special variables
• Stack
• Stack traces
• Stair-climbing puzzle
• Start from a main routine
• String append
• String case
• String comparison
• String concatenation
• String interpolation (included)
• String length
• String matching
• String prepend
• Strip a set of characters from a string
• Strip comments from a string
• Strip control codes and extended characters from a string
• Strip whitespace from a string/Top and tail
• Substring
• Substring/Top and tail
• Sudoku
• Sum and product of an array
• Sum digits of an integer
• Sum multiples of 3 and 5
• Sum of a series
• Sum of squares
• Symmetric difference
• Synchronous concurrency
• System time
• Table creation/Postal addresses
• Take notes on the command line
• Temperature conversion
• Terminal control/Clear the screen
• Terminal control/Display an extended character
• Ternary logic
• Test a function
• Text processing/1
• Text processing/2
• Text processing/Max licenses in use
• The Twelve Days of Christmas
• Tic-tac-toe
• Time a function
• Tokenize a string
• Top rank per group
• Topic variable
• Topological sort
• Topswops
• Trabb Pardo–Knuth algorithm
• Tree traversal
• Trigonometric functions
• Truncate a file
• URL decoding
• URL encoding
• Undefined values
• Unicode strings
• Universal Turing machine
• Unix/ls
• Update a configuration file
• Van der Corput sequence
• Variable size/Get
• Variable size/Set
• Variable-length quantity
• Variables
• Variadic function
• Vector products
• Verify distribution uniformity/Naive
• Vigenère cipher
• Visualize a tree
• Walk a directory/Non-recursively
• Walk a directory/Recursively
• Water collected between towers
• Web scraping
• Word wrap
• World Cup group stage
• Write float arrays to a text file
• XML/Input
• XML/Output
• XML/XPath
• Y combinator
• Zebra puzzle
• Zig-zag matrix