LFE
LFE
AboutExercisesBuild Status

242
students have developed their LFE skills on Exercism.

Students
242
Submissions
785
Mentoring Discussions
23

The LFE track needs attention ⚠️

Building

Build

Use your knowledge to build the LFE track itself

Build Test Runners

Learn More

Create Test Runners that have the single responsibility of taking a solution, running all tests and returning a standardized output.

Next goal: Get Test Runners to Version 2. LFE is currently utilising a Version 1 Test Runner. Find out more.

Usage statistics

Total Test Runner Runs
684
Test Run Pass Rate
39.2% (268)
Test Run Fail Rate
59.8% (409)
Test Run Error Rate
1.0% (7)

Build Analyzers

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Build an Analyzer for LFE: Exercism's analyzers automatically assess student's submissions and provide mentor-style commentary.

Next goal: Build an Analyzer. Find out more.

Build Representers

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Build a Representer: a bit of code that has the single responsibility of taking a solution and returning a normalized representation of it.

Next goal: Build a Representer. Find out more.

Create Practice Exercises

Learn More

Practice Exercises are exercises designed to allow students to solve an arbitrary problem, with the aim of them making use of the concepts they have learned so far.

Next goal: Implement at least 40 practice exercises. Find out more.

Usage statistics

31 active practice exercises
Started
Attempts
Completions
Mentoring requests
Hello World Hello World
113
122 (avg. 1.1)
87 (77.0%)
0 (0.0%)
Allergies Allergies
30
108 (avg. 3.6)
2 (6.7%)
0 (0.0%)
Anagram Anagram
17
45 (avg. 2.6)
10 (58.8%)
0 (0.0%)
Atbash Cipher Atbash Cipher
9
27 (avg. 3.0)
3 (33.3%)
0 (0.0%)
Bank Account Bank Account
5
53 (avg. 10.6)
0 (0.0%)
1 (20.0%)
Beer Song Beer Song
4
10 (avg. 2.5)
0 (0.0%)
0 (0.0%)
Binary Binary
7
32 (avg. 4.6)
3 (42.9%)
0 (0.0%)
Bob Bob
19
92 (avg. 4.8)
14 (73.7%)
3 (15.8%)
Circular Buffer Circular Buffer
6
57 (avg. 9.5)
1 (16.7%)
1 (16.7%)
Clock Clock
3
0 (avg. 0.0)
0 (0.0%)
0 (0.0%)
Difference of Squares Difference of Squares
5
10 (avg. 2.0)
3 (60.0%)
0 (0.0%)
ETL ETL
3
0 (avg. 0.0)
0 (0.0%)
0 (0.0%)
Gigasecond Gigasecond
4
0 (avg. 0.0)
0 (0.0%)
0 (0.0%)
Grade School Grade School
5
3 (avg. 0.6)
2 (40.0%)
0 (0.0%)
Grains Grains
9
12 (avg. 1.3)
7 (77.8%)
0 (0.0%)
Hamming Hamming
12
33 (avg. 2.8)
10 (83.3%)
1 (8.3%)
Largest Series Product Largest Series Product
3
0 (avg. 0.0)
0 (0.0%)
0 (0.0%)
Leap Leap
55
73 (avg. 1.3)
42 (76.4%)
9 (16.4%)
Luhn Luhn
3
0 (avg. 0.0)
0 (0.0%)
0 (0.0%)
Meetup Meetup
3
0 (avg. 0.0)
0 (0.0%)
0 (0.0%)
Nucleotide Count Nucleotide Count
7
6 (avg. 0.9)
5 (71.4%)
0 (0.0%)
Parallel Letter Frequency Parallel Letter Frequency
4
0 (avg. 0.0)
0 (0.0%)
0 (0.0%)
Phone Number Phone Number
6
2 (avg. 0.3)
2 (33.3%)
0 (0.0%)
RNA Transcription RNA Transcription
26
40 (avg. 1.5)
23 (88.5%)
6 (23.1%)
Robot Simulator Robot Simulator
5
2 (avg. 0.4)
2 (40.0%)
0 (0.0%)
Series Series
3
0 (avg. 0.0)
0 (0.0%)
0 (0.0%)
Space Age Space Age
8
9 (avg. 1.1)
7 (87.5%)
0 (0.0%)
Strain Strain
11
14 (avg. 1.3)
9 (81.8%)
0 (0.0%)
Sum of Multiples Sum of Multiples
14
22 (avg. 1.6)
10 (71.4%)
2 (14.3%)
Trinary Trinary
4
0 (avg. 0.0)
0 (0.0%)
0 (0.0%)
Word Count Word Count
6
3 (avg. 0.5)
3 (50.0%)
0 (0.0%)
1 deprecated practice exercises
Started
Attempts
Completions
Mentoring requests
Accumulate Accumulate
3
10 (avg. 3.3)
3 (100.0%)
2 (66.7%)
100 unimplemented practice exercises
Acronym Acronym
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Affine Cipher Affine Cipher
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All Your Base All Your Base
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Alphametics Alphametics
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Armstrong Numbers Armstrong Numbers
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Binary Search Binary Search
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Binary Search Tree Binary Search Tree
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Book Store Book Store
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Bottle Song Bottle Song
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Bowling Bowling
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Change Change
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Collatz Conjecture Collatz Conjecture
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Complex Numbers Complex Numbers
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Connect Connect
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Crypto Square Crypto Square
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Custom Set Custom Set
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D&D Character D&D Character
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DOT DSL DOT DSL
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Darts Darts
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Diamond Diamond
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Dominoes Dominoes
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Error Handling Error Handling
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Flatten Array Flatten Array
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Food Chain Food Chain
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Forth Forth
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Go Counting Go Counting
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Grep Grep
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Hangman Hangman
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High Scores High Scores
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House House
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ISBN Verifier ISBN Verifier
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Isogram Isogram
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Killer Sudoku Helper Killer Sudoku Helper
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Kindergarten Garden Kindergarten Garden
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Knapsack Knapsack
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Ledger Ledger
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Lens Person Lens Person
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Linked List Linked List
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List Ops List Ops
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Markdown Markdown
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Matching Brackets Matching Brackets
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Matrix Matrix
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Micro Blog Micro Blog
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Minesweeper Minesweeper
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Nth Prime Nth Prime
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OCR Numbers OCR Numbers
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POV POV
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PaaS I/O PaaS I/O
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Palindrome Products Palindrome Products
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Pangram Pangram
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Pascal's Triangle Pascal's Triangle
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Perfect Numbers Perfect Numbers
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Pig Latin Pig Latin
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Poker Poker
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Prime Factors Prime Factors
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Protein Translation Protein Translation
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Proverb Proverb
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Pythagorean Triplet Pythagorean Triplet
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Queen Attack Queen Attack
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REST API REST API
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Rail Fence Cipher Rail Fence Cipher
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Raindrops Raindrops
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Rational Numbers Rational Numbers
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React React
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Rectangles Rectangles
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Resistor Color Resistor Color
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Resistor Color Duo Resistor Color Duo
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Resistor Color Trio Resistor Color Trio
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Reverse String Reverse String
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Robot Name Robot Name
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Roman Numerals Roman Numerals
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Rotational Cipher Rotational Cipher
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Run-Length Encoding Run-Length Encoding
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SGF Parsing SGF Parsing
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Saddle Points Saddle Points
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Satellite Satellite
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Say Say
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Scale Generator Scale Generator
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Scrabble Score Scrabble Score
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Secret Handshake Secret Handshake
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Sieve Sieve
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Simple Cipher Simple Cipher
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Simple Linked List Simple Linked List
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Spiral Matrix Spiral Matrix
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Square Root Square Root
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State of Tic-Tac-Toe State of Tic-Tac-Toe
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Sublist Sublist
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Tournament Tournament
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Transpose Transpose
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Tree Building Tree Building
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Triangle Triangle
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Twelve Days Twelve Days
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Two Bucket Two Bucket
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Two-Fer Two-Fer
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Variable Length Quantity Variable Length Quantity
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Word Search Word Search
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Wordy Wordy
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Yacht Yacht
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Zebra Puzzle Zebra Puzzle
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Zipper Zipper
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