diff --git a/exercises/accumulate/README.md b/exercises/accumulate/README.md new file mode 100644 index 0000000..582e21a --- /dev/null +++ b/exercises/accumulate/README.md @@ -0,0 +1,65 @@ +# Accumulate + +Implement the `accumulate` operation, which, given a collection and an +operation to perform on each element of the collection, returns a new +collection containing the result of applying that operation to each element of +the input collection. + +Given the collection of numbers: + +- 1, 2, 3, 4, 5 + +And the operation: + +- square a number (`x => x * x`) + +Your code should be able to produce the collection of squares: + +- 1, 4, 9, 16, 25 + +Check out the test suite to see the expected function signature. + +## Restrictions + +Keep your hands off that collect/map/fmap/whatchamacallit functionality +provided by your standard library! +Solve this one yourself using other basic tools instead. + +Lisp specific: it's perfectly fine to use `MAPCAR` or the equivalent, +as this is idiomatic Lisp, not a library function. + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +Conversation with James Edward Gray II [https://twitter.com/jeg2](https://twitter.com/jeg2) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/allergies/README.md b/exercises/allergies/README.md new file mode 100644 index 0000000..7bd8616 --- /dev/null +++ b/exercises/allergies/README.md @@ -0,0 +1,67 @@ +# Allergies + +Given a person's allergy score, determine whether or not they're allergic to a given item, and their full list of allergies. + +An allergy test produces a single numeric score which contains the +information about all the allergies the person has (that they were +tested for). + +The list of items (and their value) that were tested are: + +* eggs (1) +* peanuts (2) +* shellfish (4) +* strawberries (8) +* tomatoes (16) +* chocolate (32) +* pollen (64) +* cats (128) + +So if Tom is allergic to peanuts and chocolate, he gets a score of 34. + +Now, given just that score of 34, your program should be able to say: + +- Whether Tom is allergic to any one of those allergens listed above. +- All the allergens Tom is allergic to. + +Note: a given score may include allergens **not** listed above (i.e. +allergens that score 256, 512, 1024, etc.). Your program should +ignore those components of the score. For example, if the allergy +score is 257, your program should only report the eggs (1) allergy. + + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +Jumpstart Lab Warm-up [http://jumpstartlab.com](http://jumpstartlab.com) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/anagram/README.md b/exercises/anagram/README.md new file mode 100644 index 0000000..371718f --- /dev/null +++ b/exercises/anagram/README.md @@ -0,0 +1,43 @@ +# Anagram + +Given a word and a list of possible anagrams, select the correct sublist. + +Given `"listen"` and a list of candidates like `"enlists" "google" +"inlets" "banana"` the program should return a list containing +`"inlets"`. + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +Inspired by the Extreme Startup game [https://github.com/rchatley/extreme_startup](https://github.com/rchatley/extreme_startup) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/atbash-cipher/README.md b/exercises/atbash-cipher/README.md new file mode 100644 index 0000000..5e9158a --- /dev/null +++ b/exercises/atbash-cipher/README.md @@ -0,0 +1,64 @@ +# Atbash Cipher + +Create an implementation of the atbash cipher, an ancient encryption system created in the Middle East. + +The Atbash cipher is a simple substitution cipher that relies on +transposing all the letters in the alphabet such that the resulting +alphabet is backwards. The first letter is replaced with the last +letter, the second with the second-last, and so on. + +An Atbash cipher for the Latin alphabet would be as follows: + +```plain +Plain: abcdefghijklmnopqrstuvwxyz +Cipher: zyxwvutsrqponmlkjihgfedcba +``` + +It is a very weak cipher because it only has one possible key, and it is +a simple monoalphabetic substitution cipher. However, this may not have +been an issue in the cipher's time. + +Ciphertext is written out in groups of fixed length, the traditional group size +being 5 letters, and punctuation is excluded. This is to make it harder to guess +things based on word boundaries. + +## Examples +- Encoding `test` gives `gvhg` +- Decoding `gvhg` gives `test` +- Decoding `gsvjf rxpyi ldmul cqfnk hlevi gsvoz abwlt` gives `thequickbrownfoxjumpsoverthelazydog` + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +Wikipedia [http://en.wikipedia.org/wiki/Atbash](http://en.wikipedia.org/wiki/Atbash) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/bob/README.md b/exercises/bob/README.md new file mode 100644 index 0000000..e3c5a08 --- /dev/null +++ b/exercises/bob/README.md @@ -0,0 +1,48 @@ +# Bob + +Bob is a lackadaisical teenager. In conversation, his responses are very limited. + +Bob answers 'Sure.' if you ask him a question. + +He answers 'Whoa, chill out!' if you yell at him. + +He says 'Fine. Be that way!' if you address him without actually saying +anything. + +He answers 'Whatever.' to anything else. + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +Inspired by the 'Deaf Grandma' exercise in Chris Pine's Learn to Program tutorial. [http://pine.fm/LearnToProgram/?Chapter=06](http://pine.fm/LearnToProgram/?Chapter=06) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/difference-of-squares/README.md b/exercises/difference-of-squares/README.md new file mode 100644 index 0000000..a2902b8 --- /dev/null +++ b/exercises/difference-of-squares/README.md @@ -0,0 +1,49 @@ +# Difference Of Squares + +Find the difference between the square of the sum and the sum of the squares of the first N natural numbers. + +The square of the sum of the first ten natural numbers is +(1 + 2 + ... + 10)² = 55² = 3025. + +The sum of the squares of the first ten natural numbers is +1² + 2² + ... + 10² = 385. + +Hence the difference between the square of the sum of the first +ten natural numbers and the sum of the squares of the first ten +natural numbers is 3025 - 385 = 2640. + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +Problem 6 at Project Euler [http://projecteuler.net/problem=6](http://projecteuler.net/problem=6) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/etl/README.md b/exercises/etl/README.md new file mode 100644 index 0000000..58c82b5 --- /dev/null +++ b/exercises/etl/README.md @@ -0,0 +1,81 @@ +# Etl + +We are going to do the `Transform` step of an Extract-Transform-Load. + +### ETL +Extract-Transform-Load (ETL) is a fancy way of saying, "We have some crufty, legacy data over in this system, and now we need it in this shiny new system over here, so +we're going to migrate this." + +(Typically, this is followed by, "We're only going to need to run this +once." That's then typically followed by much forehead slapping and +moaning about how stupid we could possibly be.) + +### The goal +We're going to extract some scrabble scores from a legacy system. + +The old system stored a list of letters per score: + +- 1 point: "A", "E", "I", "O", "U", "L", "N", "R", "S", "T", +- 2 points: "D", "G", +- 3 points: "B", "C", "M", "P", +- 4 points: "F", "H", "V", "W", "Y", +- 5 points: "K", +- 8 points: "J", "X", +- 10 points: "Q", "Z", + +The shiny new scrabble system instead stores the score per letter, which +makes it much faster and easier to calculate the score for a word. It +also stores the letters in lower-case regardless of the case of the +input letters: + +- "a" is worth 1 point. +- "b" is worth 3 points. +- "c" is worth 3 points. +- "d" is worth 2 points. +- Etc. + +Your mission, should you choose to accept it, is to transform the legacy data +format to the shiny new format. + +### Notes + +A final note about scoring, Scrabble is played around the world in a +variety of languages, each with its own unique scoring table. For +example, an "E" is scored at 2 in the Māori-language version of the +game while being scored at 4 in the Hawaiian-language version. + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +The Jumpstart Lab team [http://jumpstartlab.com](http://jumpstartlab.com) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/gigasecond/README.md b/exercises/gigasecond/README.md new file mode 100644 index 0000000..6a006fd --- /dev/null +++ b/exercises/gigasecond/README.md @@ -0,0 +1,41 @@ +# Gigasecond + +Calculate the moment when someone has lived for 10^9 seconds. + +A gigasecond is 10^9 (1,000,000,000) seconds. + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +Chapter 9 in Chris Pine's online Learn to Program tutorial. [http://pine.fm/LearnToProgram/?Chapter=09](http://pine.fm/LearnToProgram/?Chapter=09) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/grade-school/README.md b/exercises/grade-school/README.md new file mode 100644 index 0000000..fa6dc10 --- /dev/null +++ b/exercises/grade-school/README.md @@ -0,0 +1,72 @@ +# Grade School + +Given students' names along with the grade that they are in, create a roster +for the school. + +In the end, you should be able to: + +- Add a student's name to the roster for a grade + - "Add Jim to grade 2." + - "OK." +- Get a list of all students enrolled in a grade + - "Which students are in grade 2?" + - "We've only got Jim just now." +- Get a sorted list of all students in all grades. Grades should sort + as 1, 2, 3, etc., and students within a grade should be sorted + alphabetically by name. + - "Who all is enrolled in school right now?" + - "Grade 1: Anna, Barb, and Charlie. Grade 2: Alex, Peter, and Zoe. + Grade 3…" + +Note that all our students only have one name. (It's a small town, what +do you want?) + + +## For bonus points + +Did you get the tests passing and the code clean? If you want to, these +are some additional things you could try: + +- If you're working in a language with mutable data structures and your + implementation allows outside code to mutate the school's internal DB + directly, see if you can prevent this. Feel free to introduce additional + tests. + +Then please share your thoughts in a comment on the submission. Did this +experiment make the code better? Worse? Did you learn anything from it? + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +A pairing session with Phil Battos at gSchool [http://gschool.it](http://gschool.it) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/grains/README.md b/exercises/grains/README.md new file mode 100644 index 0000000..904dd4b --- /dev/null +++ b/exercises/grains/README.md @@ -0,0 +1,64 @@ +# Grains + +Calculate the number of grains of wheat on a chessboard given that the number +on each square doubles. + +There once was a wise servant who saved the life of a prince. The king +promised to pay whatever the servant could dream up. Knowing that the +king loved chess, the servant told the king he would like to have grains +of wheat. One grain on the first square of a chess board. Two grains on +the next. Four on the third, and so on. + +There are 64 squares on a chessboard. + +Write code that shows: +- how many grains were on each square, and +- the total number of grains + + +## For bonus points + +Did you get the tests passing and the code clean? If you want to, these +are some additional things you could try: + +- Optimize for speed. +- Optimize for readability. + +Then please share your thoughts in a comment on the submission. Did this +experiment make the code better? Worse? Did you learn anything from it? + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +JavaRanch Cattle Drive, exercise 6 [http://www.javaranch.com/grains.jsp](http://www.javaranch.com/grains.jsp) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/hamming/README.md b/exercises/hamming/README.md new file mode 100644 index 0000000..aee3642 --- /dev/null +++ b/exercises/hamming/README.md @@ -0,0 +1,72 @@ +# Hamming + +Calculate the Hamming difference between two DNA strands. + +A mutation is simply a mistake that occurs during the creation or +copying of a nucleic acid, in particular DNA. Because nucleic acids are +vital to cellular functions, mutations tend to cause a ripple effect +throughout the cell. Although mutations are technically mistakes, a very +rare mutation may equip the cell with a beneficial attribute. In fact, +the macro effects of evolution are attributable by the accumulated +result of beneficial microscopic mutations over many generations. + +The simplest and most common type of nucleic acid mutation is a point +mutation, which replaces one base with another at a single nucleotide. + +By counting the number of differences between two homologous DNA strands +taken from different genomes with a common ancestor, we get a measure of +the minimum number of point mutations that could have occurred on the +evolutionary path between the two strands. + +This is called the 'Hamming distance'. + +It is found by comparing two DNA strands and counting how many of the +nucleotides are different from their equivalent in the other string. + + GAGCCTACTAACGGGAT + CATCGTAATGACGGCCT + ^ ^ ^ ^ ^ ^^ + +The Hamming distance between these two DNA strands is 7. + +# Implementation notes + +The Hamming distance is only defined for sequences of equal length. This means +that based on the definition, each language could deal with getting sequences +of equal length differently. + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +The Calculating Point Mutations problem at Rosalind [http://rosalind.info/problems/hamm/](http://rosalind.info/problems/hamm/) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/hello-world/README.md b/exercises/hello-world/README.md new file mode 100644 index 0000000..d1fe144 --- /dev/null +++ b/exercises/hello-world/README.md @@ -0,0 +1,51 @@ +# Hello World + +The classical introductory exercise. Just say "Hello, World!". + +["Hello, World!"](http://en.wikipedia.org/wiki/%22Hello,_world!%22_program) is +the traditional first program for beginning programming in a new language +or environment. + +The objectives are simple: + +- Write a function that returns the string "Hello, World!". +- Run the test suite and make sure that it succeeds. +- Submit your solution and check it at the website. + +If everything goes well, you will be ready to fetch your first real exercise. + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +This is an exercise to introduce users to using Exercism [http://en.wikipedia.org/wiki/%22Hello,_world!%22_program](http://en.wikipedia.org/wiki/%22Hello,_world!%22_program) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/largest-series-product/README.md b/exercises/largest-series-product/README.md new file mode 100644 index 0000000..623bf2e --- /dev/null +++ b/exercises/largest-series-product/README.md @@ -0,0 +1,50 @@ +# Largest Series Product + +Given a string of digits, calculate the largest product for a contiguous +substring of digits of length n. + +For example, for the input `'1027839564'`, the largest product for a +series of 3 digits is 270 (9 * 5 * 6), and the largest product for a +series of 5 digits is 7560 (7 * 8 * 3 * 9 * 5). + +Note that these series are only required to occupy *adjacent positions* +in the input; the digits need not be *numerically consecutive*. + +For the input `'73167176531330624919225119674426574742355349194934'`, +the largest product for a series of 6 digits is 23520. + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +A variation on Problem 8 at Project Euler [http://projecteuler.net/problem=8](http://projecteuler.net/problem=8) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/leap/README.md b/exercises/leap/README.md new file mode 100644 index 0000000..f6516f7 --- /dev/null +++ b/exercises/leap/README.md @@ -0,0 +1,63 @@ +# Leap + +Given a year, report if it is a leap year. + +The tricky thing here is that a leap year in the Gregorian calendar occurs: + +```plain +on every year that is evenly divisible by 4 + except every year that is evenly divisible by 100 + unless the year is also evenly divisible by 400 +``` + +For example, 1997 is not a leap year, but 1996 is. 1900 is not a leap +year, but 2000 is. + +If your language provides a method in the standard library that does +this look-up, pretend it doesn't exist and implement it yourself. + +## Notes + +Though our exercise adopts some very simple rules, there is more to +learn! + +For a delightful, four minute explanation of the whole leap year +phenomenon, go watch [this youtube video][video]. + +[video]: http://www.youtube.com/watch?v=xX96xng7sAE + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +JavaRanch Cattle Drive, exercise 3 [http://www.javaranch.com/leap.jsp](http://www.javaranch.com/leap.jsp) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/list-ops/README.md b/exercises/list-ops/README.md new file mode 100644 index 0000000..c3f9926 --- /dev/null +++ b/exercises/list-ops/README.md @@ -0,0 +1,40 @@ +# List Ops + +Implement basic list operations. + +In functional languages list operations like `length`, `map`, and +`reduce` are very common. Implement a series of basic list operations, +without using existing functions. + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/nucleotide-count/README.md b/exercises/nucleotide-count/README.md new file mode 100644 index 0000000..fa1ae02 --- /dev/null +++ b/exercises/nucleotide-count/README.md @@ -0,0 +1,63 @@ +# Nucleotide Count + +Given a DNA string, compute how many times each nucleotide occurs in the string. + +DNA is represented by an alphabet of the following symbols: 'A', 'C', +'G', and 'T'. + +Each symbol represents a nucleotide, which is a fancy name for the +particular molecules that happen to make up a large part of DNA. + +Shortest intro to biochemistry EVAR: + +- twigs are to birds nests as +- nucleotides are to DNA and RNA as +- amino acids are to proteins as +- sugar is to starch as +- oh crap lipids + +I'm not going to talk about lipids because they're crazy complex. + +So back to nucleotides. + +DNA contains four types of them: adenine (`A`), cytosine (`C`), guanine +(`G`), and thymine (`T`). + +RNA contains a slightly different set of nucleotides, but we don't care +about that for now. + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +The Calculating DNA Nucleotides_problem at Rosalind [http://rosalind.info/problems/dna/](http://rosalind.info/problems/dna/) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/pangram/README.md b/exercises/pangram/README.md new file mode 100644 index 0000000..0e2b90a --- /dev/null +++ b/exercises/pangram/README.md @@ -0,0 +1,45 @@ +# Pangram + +Determine if a sentence is a pangram. A pangram (Greek: παν γράμμα, pan gramma, +"every letter") is a sentence using every letter of the alphabet at least once. +The best known English pangram is: +> The quick brown fox jumps over the lazy dog. + +The alphabet used consists of ASCII letters `a` to `z`, inclusive, and is case +insensitive. Input will not contain non-ASCII symbols. + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +Wikipedia [https://en.wikipedia.org/wiki/Pangram](https://en.wikipedia.org/wiki/Pangram) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/phone-number/README.md b/exercises/phone-number/README.md new file mode 100644 index 0000000..89bc001 --- /dev/null +++ b/exercises/phone-number/README.md @@ -0,0 +1,64 @@ +# Phone Number + +Clean up user-entered phone numbers so that they can be sent SMS messages. + +The **North American Numbering Plan (NANP)** is a telephone numbering system used by many countries in North America like the United States, Canada or Bermuda. All NANP-countries share the same international country code: `1`. + +NANP numbers are ten-digit numbers consisting of a three-digit Numbering Plan Area code, commonly known as *area code*, followed by a seven-digit local number. The first three digits of the local number represent the *exchange code*, followed by the unique four-digit number which is the *subscriber number*. + + +The format is usually represented as +``` +(NXX)-NXX-XXXX +``` +where `N` is any digit from 2 through 9 and `X` is any digit from 0 through 9. + +Your task is to clean up differently formated telephone numbers by removing punctuation and the country code (1) if present. + +For example, the inputs +- `+1 (613)-995-0253` +- `613-995-0253` +- `1 613 995 0253` +- `613.995.0253` + +should all produce the output + +`6139950253` + +**Note:** As this exercise only deals with telephone numbers used in NANP-countries, only 1 is considered a valid country code. + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +Event Manager by JumpstartLab [http://tutorials.jumpstartlab.com/projects/eventmanager.html](http://tutorials.jumpstartlab.com/projects/eventmanager.html) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/raindrops/README.md b/exercises/raindrops/README.md new file mode 100644 index 0000000..ed1be21 --- /dev/null +++ b/exercises/raindrops/README.md @@ -0,0 +1,54 @@ +# Raindrops + +Convert a number to a string, the contents of which depend on the number's factors. + +- If the number has 3 as a factor, output 'Pling'. +- If the number has 5 as a factor, output 'Plang'. +- If the number has 7 as a factor, output 'Plong'. +- If the number does not have 3, 5, or 7 as a factor, + just pass the number's digits straight through. + +## Examples + +- 28's factors are 1, 2, 4, **7**, 14, 28. + - In raindrop-speak, this would be a simple "Plong". +- 30's factors are 1, 2, **3**, **5**, 6, 10, 15, 30. + - In raindrop-speak, this would be a "PlingPlang". +- 34 has four factors: 1, 2, 17, and 34. + - In raindrop-speak, this would be "34". + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +A variation on a famous interview question intended to weed out potential candidates. [http://jumpstartlab.com](http://jumpstartlab.com) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/rna-transcription/README.md b/exercises/rna-transcription/README.md new file mode 100644 index 0000000..68d1064 --- /dev/null +++ b/exercises/rna-transcription/README.md @@ -0,0 +1,55 @@ +# Rna Transcription + +Given a DNA strand, return its RNA complement (per RNA transcription). + +Both DNA and RNA strands are a sequence of nucleotides. + +The four nucleotides found in DNA are adenine (**A**), cytosine (**C**), +guanine (**G**) and thymine (**T**). + +The four nucleotides found in RNA are adenine (**A**), cytosine (**C**), +guanine (**G**) and uracil (**U**). + +Given a DNA strand, its transcribed RNA strand is formed by replacing +each nucleotide with its complement: + +* `G` -> `C` +* `C` -> `G` +* `T` -> `A` +* `A` -> `U` + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +Rosalind [http://rosalind.info/problems/rna](http://rosalind.info/problems/rna) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/robot-simulator/README.md b/exercises/robot-simulator/README.md new file mode 100644 index 0000000..b587984 --- /dev/null +++ b/exercises/robot-simulator/README.md @@ -0,0 +1,64 @@ +# Robot Simulator + +Write a robot simulator. + +A robot factory's test facility needs a program to verify robot movements. + +The robots have three possible movements: + +- turn right +- turn left +- advance + +Robots are placed on a hypothetical infinite grid, facing a particular +direction (north, east, south, or west) at a set of {x,y} coordinates, +e.g., {3,8}, with coordinates increasing to the north and east. + +The robot then receives a number of instructions, at which point the +testing facility verifies the robot's new position, and in which +direction it is pointing. + +- The letter-string "RAALAL" means: + - Turn right + - Advance twice + - Turn left + - Advance once + - Turn left yet again +- Say a robot starts at {7, 3} facing north. Then running this stream + of instructions should leave it at {9, 4} facing west. + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +Inspired by an interview question at a famous company. + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/roman-numerals/README.md b/exercises/roman-numerals/README.md new file mode 100644 index 0000000..8985dc0 --- /dev/null +++ b/exercises/roman-numerals/README.md @@ -0,0 +1,79 @@ +# Roman Numerals + +Write a function to convert from normal numbers to Roman Numerals. + +The Romans were a clever bunch. They conquered most of Europe and ruled +it for hundreds of years. They invented concrete and straight roads and +even bikinis. One thing they never discovered though was the number +zero. This made writing and dating extensive histories of their exploits +slightly more challenging, but the system of numbers they came up with +is still in use today. For example the BBC uses Roman numerals to date +their programmes. + +The Romans wrote numbers using letters - I, V, X, L, C, D, M. (notice +these letters have lots of straight lines and are hence easy to hack +into stone tablets). + +``` + 1 => I +10 => X + 7 => VII +``` + +There is no need to be able to convert numbers larger than about 3000. +(The Romans themselves didn't tend to go any higher) + +Wikipedia says: Modern Roman numerals ... are written by expressing each +digit separately starting with the left most digit and skipping any +digit with a value of zero. + +To see this in practice, consider the example of 1990. + +In Roman numerals 1990 is MCMXC: + +1000=M +900=CM +90=XC + +2008 is written as MMVIII: + +2000=MM +8=VIII + +See also: http://www.novaroma.org/via_romana/numbers.html + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +The Roman Numeral Kata [http://codingdojo.org/cgi-bin/index.pl?KataRomanNumerals](http://codingdojo.org/cgi-bin/index.pl?KataRomanNumerals) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/run-length-encoding/README.md b/exercises/run-length-encoding/README.md new file mode 100644 index 0000000..c03a5cc --- /dev/null +++ b/exercises/run-length-encoding/README.md @@ -0,0 +1,60 @@ +# Run Length Encoding + +Implement run-length encoding and decoding. + +Run-length encoding (RLE) is a simple form of data compression, where runs +(consecutive data elements) are replaced by just one data value and count. + +For example we can represent the original 53 characters with only 13. + +``` +"WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWB" -> "12WB12W3B24WB" +``` + +RLE allows the original data to be perfectly reconstructed from +the compressed data, which makes it a lossless data compression. + +``` +"AABCCCDEEEE" -> "2AB3CD4E" -> "AABCCCDEEEE" +``` + +For simplicity, you can assume that the unencoded string will only contain +the letters A through Z (either lower or upper case) and whitespace. This way +data to be encoded will never contain any numbers and numbers inside data to +be decoded always represent the count for the following character. + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +Wikipedia [https://en.wikipedia.org/wiki/Run-length_encoding](https://en.wikipedia.org/wiki/Run-length_encoding) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/say/README.md b/exercises/say/README.md new file mode 100644 index 0000000..d088322 --- /dev/null +++ b/exercises/say/README.md @@ -0,0 +1,99 @@ +# Say + +Given a number from 0 to 999,999,999,999, spell out that number in English. + +## Step 1 + +Handle the basic case of 0 through 99. + +If the input to the program is `22`, then the output should be +`'twenty-two'`. + +Your program should complain loudly if given a number outside the +blessed range. + +Some good test cases for this program are: + +- 0 +- 14 +- 50 +- 98 +- -1 +- 100 + +### Extension + +If you're on a Mac, shell out to Mac OS X's `say` program to talk out +loud. + +## Step 2 + +Implement breaking a number up into chunks of thousands. + +So `1234567890` should yield a list like 1, 234, 567, and 890, while the +far simpler `1000` should yield just 1 and 0. + +The program must also report any values that are out of range. + +## Step 3 + +Now handle inserting the appropriate scale word between those chunks. + +So `1234567890` should yield `'1 billion 234 million 567 thousand 890'` + +The program must also report any values that are out of range. It's +fine to stop at "trillion". + +## Step 4 + +Put it all together to get nothing but plain English. + +`12345` should give `twelve thousand three hundred forty-five`. + +The program must also report any values that are out of range. + +### Extensions + +Use _and_ (correctly) when spelling out the number in English: + +- 14 becomes "fourteen". +- 100 becomes "one hundred". +- 120 becomes "one hundred and twenty". +- 1002 becomes "one thousand and two". +- 1323 becomes "one thousand three hundred and twenty-three". + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +A variation on JavaRanch CattleDrive, exercise 4a [http://www.javaranch.com/say.jsp](http://www.javaranch.com/say.jsp) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/scrabble-score/README.md b/exercises/scrabble-score/README.md new file mode 100644 index 0000000..5207d59 --- /dev/null +++ b/exercises/scrabble-score/README.md @@ -0,0 +1,74 @@ +# Scrabble Score + +Given a word, compute the scrabble score for that word. + +## Letter Values + +You'll need these: + +```plain +Letter Value +A, E, I, O, U, L, N, R, S, T 1 +D, G 2 +B, C, M, P 3 +F, H, V, W, Y 4 +K 5 +J, X 8 +Q, Z 10 +``` + +## Examples +"cabbage" should be scored as worth 14 points: + +- 3 points for C +- 1 point for A, twice +- 3 points for B, twice +- 2 points for G +- 1 point for E + +And to total: + +- `3 + 2*1 + 2*3 + 2 + 1` +- = `3 + 2 + 6 + 3` +- = `5 + 9` +- = 14 + +## Extensions +- You can play a double or a triple letter. +- You can play a double or a triple word. + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +Inspired by the Extreme Startup game [https://github.com/rchatley/extreme_startup](https://github.com/rchatley/extreme_startup) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/series/README.md b/exercises/series/README.md new file mode 100644 index 0000000..941569b --- /dev/null +++ b/exercises/series/README.md @@ -0,0 +1,57 @@ +# Series + +Given a string of digits, output all the contiguous substrings of length `n` in +that string. + +For example, the string "49142" has the following 3-digit series: + +- 491 +- 914 +- 142 + +And the following 4-digit series: + +- 4914 +- 9142 + +And if you ask for a 6-digit series from a 5-digit string, you deserve +whatever you get. + +Note that these series are only required to occupy *adjacent positions* +in the input; the digits need not be *numerically consecutive*. + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +A subset of the Problem 8 at Project Euler [http://projecteuler.net/problem=8](http://projecteuler.net/problem=8) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/space-age/README.md b/exercises/space-age/README.md new file mode 100644 index 0000000..52f0cf2 --- /dev/null +++ b/exercises/space-age/README.md @@ -0,0 +1,54 @@ +# Space Age + +Given an age in seconds, calculate how old someone would be on: + + - Earth: orbital period 365.25 Earth days, or 31557600 seconds + - Mercury: orbital period 0.2408467 Earth years + - Venus: orbital period 0.61519726 Earth years + - Mars: orbital period 1.8808158 Earth years + - Jupiter: orbital period 11.862615 Earth years + - Saturn: orbital period 29.447498 Earth years + - Uranus: orbital period 84.016846 Earth years + - Neptune: orbital period 164.79132 Earth years + +So if you were told someone were 1,000,000,000 seconds old, you should +be able to say that they're 31 Earth-years old. + +If you're wondering why Pluto didn't make the cut, go watch [this +youtube video](http://www.youtube.com/watch?v=Z_2gbGXzFbs). + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +Partially inspired by Chapter 1 in Chris Pine's online Learn to Program tutorial. [http://pine.fm/LearnToProgram/?Chapter=01](http://pine.fm/LearnToProgram/?Chapter=01) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/strain/README.md b/exercises/strain/README.md new file mode 100644 index 0000000..44b5acb --- /dev/null +++ b/exercises/strain/README.md @@ -0,0 +1,70 @@ +# Strain + +Implement the `keep` and `discard` operation on collections. Given a collection +and a predicate on the collection's elements, `keep` returns a new collection +containing those elements where the predicate is true, while `discard` returns +a new collection containing those elements where the predicate is false. + +For example, given the collection of numbers: + +- 1, 2, 3, 4, 5 + +And the predicate: + +- is the number even? + +Then your keep operation should produce: + +- 2, 4 + +While your discard operation should produce: + +- 1, 3, 5 + +Note that the union of keep and discard is all the elements. + +The functions may be called `keep` and `discard`, or they may need different +names in order to not clash with existing functions or concepts in your +language. + +## Restrictions + +Keep your hands off that filter/reject/whatchamacallit functionality +provided by your standard library! Solve this one yourself using other +basic tools instead. + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +Conversation with James Edward Gray II [https://twitter.com/jeg2](https://twitter.com/jeg2) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/sublist/README.md b/exercises/sublist/README.md new file mode 100644 index 0000000..39c77af --- /dev/null +++ b/exercises/sublist/README.md @@ -0,0 +1,51 @@ +# Sublist + +Given two lists determine if the first list is contained within the second +list, if the second list is contained within the first list, if both lists are +contained within each other or if none of these are true. + +Specifically, a list A is a sublist of list B if by dropping 0 or more elements +from the front of B and 0 or more elements from the back of B you get a list +that's completely equal to A. + +Examples: + + * A = [1, 2, 3], B = [1, 2, 3, 4, 5], A is a sublist of B + * A = [3, 4, 5], B = [1, 2, 3, 4, 5], A is a sublist of B + * A = [3, 4], B = [1, 2, 3, 4, 5], A is a sublist of B + * A = [1, 2, 3], B = [1, 2, 3], A is equal to B + * A = [1, 2, 3, 4, 5], B = [2, 3, 4], A is a superlist of B + * A = [1, 2, 4], B = [1, 2, 3, 4, 5], A is not a superlist of, sublist of or equal to B + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/sum-of-multiples/README.md b/exercises/sum-of-multiples/README.md new file mode 100644 index 0000000..f011578 --- /dev/null +++ b/exercises/sum-of-multiples/README.md @@ -0,0 +1,48 @@ +# Sum Of Multiples + +Given a number, find the sum of all the multiples of particular numbers up to +but not including that number. + +If we list all the natural numbers up to but not including 20 that are +multiples of either 3 or 5, we get 3, 5, 6 and 9, 10, 12, 15, and 18. + +The sum of these multiples is 78. + +Given a number, find the sum of the multiples of a given set of numbers, +up to but not including that number. + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +A variation on Problem 1 at Project Euler [http://projecteuler.net/problem=1](http://projecteuler.net/problem=1) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/triangle/README.md b/exercises/triangle/README.md new file mode 100644 index 0000000..0685231 --- /dev/null +++ b/exercises/triangle/README.md @@ -0,0 +1,56 @@ +# Triangle + +Determine if a triangle is equilateral, isosceles, or scalene. + +An _equilateral_ triangle has all three sides the same length.
+An _isosceles_ triangle has at least two sides the same length. (It is sometimes +specified as having exactly two sides the same length, but for the purposes of +this exercise we'll say at least two.)
+A _scalene_ triangle has all sides of different lengths. + +## Note + +For a shape to be a triangle at all, all sides have to be of length > 0, and +the sum of the lengths of any two sides must be greater than or equal to the +length of the third side. See [Triangle Inequality](https://en.wikipedia.org/wiki/Triangle_inequality). + +## Dig Deeper + +The case where the sum of the lengths of two sides _equals_ that of the +third is known as a _degenerate_ triangle - it has zero area and looks like +a single line. Feel free to add your own code/tests to check for degenerate triangles. +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +The Ruby Koans triangle project, parts 1 & 2 [http://rubykoans.com](http://rubykoans.com) + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise. diff --git a/exercises/word-count/README.md b/exercises/word-count/README.md new file mode 100644 index 0000000..1e0f2ed --- /dev/null +++ b/exercises/word-count/README.md @@ -0,0 +1,49 @@ +# Word Count + +Given a phrase, count the occurrences of each word in that phrase. + +For example for the input `"olly olly in come free"` + +```plain +olly: 2 +in: 1 +come: 1 +free: 1 +``` + + +## Elm Installation + +Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm +installation and learning resources. + +## Writing the Code + +The first time you start an exercise, you'll need to ensure you have the +appropriate dependencies installed. + +```bash +$ npm install +``` + +Execute the tests with: + +```bash +$ npm test +``` + +Automatically run tests again when you save changes: + +```bash +$ npm run watch +``` + +As you work your way through the test suite, be sure to remove the `skip <|` +calls from each test until you get them all passing! + +## Source + +This is a classic toy problem, but we were reminded of it by seeing it in the Go Tour. + +## Submitting Incomplete Solutions +It's possible to submit an incomplete solution so you can see how others have completed the exercise.