evantianx / codewars-haskell

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codewars-haskell's Issues

Categorize New Member

The Western Suburbs Croquet Club has two categories of membership, Senior and Open. They would like your help with an application form that will tell prospective members which category they will be placed.

To be a senior, a member must be at least 55 years old and have a handicap greater than 7. In this croquet club, handicaps range from -2 to +26; the better the player the lower the handicap.

Input

Input will consist of a list of lists containing two items each. Each list contains information for a single potential member. Information consists of an integer for the person's age and an integer for the person's handicap.

Note for F#: The input will be of (int list list) which is a List>

Example Input

[(18, 20),(45, 2),(61, 12),(37, 6),(21, 21),(78, 9)]

Output

Output will consist of a list of string values (in Haskell: Open or Senior) stating whether the respective member is to be placed in the senior or open category.

Example Output

[Open, Open, Senior, Open, Open, Senior]

Convert string to camel case

Complete the method/function so that it converts dash/underscore delimited words into camel casing. The first word within the output should be capitalized only if the original word was capitalized.

Examples

toCamelCase "the-stealth-warrior" -- returns "theStealthWarrior"

toCamelCase "The_Stealth_Warrior" -- returns "TheStealthWarrior"

Write Number in Expanded Form

You will be given a number and you will need to return it as a string in Expanded Form. For example:

expandedForm 12    -- Should return '10 + 2'
expandedForm 42    -- Should return '40 + 2'
expandedForm 70304 -- Should return '70000 + 300 + 4'

NOTE: All numbers will be whole numbers greater than 0.

You're a square!

Task

Given an integral number, determine if it's a square number

Solutions

isSquare :: Integral n => n -> Bool
isSquare n = let sr = round $ sqrt $ fromIntegral n in sr * sr == n

Take a Number And Sum Its Digits Raised To The Consecutive Powers And ....¡Eureka!!

The number 89 is the first integer with more than one digit that fulfills the property partially introduced in the title of this kata. What's the use of saying "Eureka"? Because this sum gives the same number.

In effect: 89 = 8^1 + 9^2

The next number in having this property is 135.

See this property again: 135 = 1^1 + 3^2 + 5^3

We need a function to collect these numbers, that may receive two integers a, b that defines the range [a, b] (inclusive) and outputs a list of the sorted numbers in the range that fulfills the property described above.

Let's see some cases:

sum_dig_pow(1, 10) == [1, 2, 3, 4, 5, 6, 7, 8, 9]

sum_dig_pow(1, 100) == [1, 2, 3, 4, 5, 6, 7, 8, 9, 89]

If there are no numbers of this kind in the range [a, b] the function should output an empty list.

sum_dig_pow(90, 100) == []

Enjoy it!!

Fold an array

In this kata you have to write a method that folds a given array of integers by the middle x-times.

An example says more than thousand words:

Fold 1-times:
[1,2,3,4,5] -> [6,6,3]

A little visualization (NOT for the algorithm but for the idea of folding):

 Step 1         Step 2        Step 3       Step 4       Step5
                     5/           5|         5\          
                    4/            4|          4\      
1 2 3 4 5      1 2 3/         1 2 3|       1 2 3\       6 6 3
----*----      ----*          ----*        ----*        ----*


Fold 2-times:
[1,2,3,4,5] -> [9,6]

As you see, if the count of numbers is odd, the middle number will stay. Otherwise the fold-point is between the middle-numbers, so all numbers would be added in a way.

The array will always contain numbers and will never be null. The parameter runs will always be a positive integer greater than 0 and says how many runs of folding your method has to do.

If an array with one element is folded, it stays as the same array.

The input array should not be modified!

Mumbling

Examples:

accum "abcd"    -- "A-Bb-Ccc-Dddd"
accum "RqaEzty" -- "R-Qq-Aaa-Eeee-Zzzzz-Tttttt-Yyyyyyy"
accum "cwAt"    -- "C-Ww-Aaa-Tttt"

The parameter of accum is a string which includes only letters from a..z and A..Z.

Valid Phone Number

Description:

Write a function that accepts a string, and returns true if it is in the form of a phone number.
Assume that any integer from 0-9 in any of the spots will produce a valid phone number.

Only worry about the following format:
[phone] (don't forget the space after the close parentheses)

Examples:

validPhoneNumber("[phone]")  =>  returns true
validPhoneNumber("(1111)555 2345")  => returns false
validPhoneNumber("[phone]")  => returns false

Split Strings

Complete the solution so that it splits the string into pairs of two characters. If the string contains an odd number of characters then it should replace the missing second character of the final pair with an underscore ('_').

Examples:

solution "abc" `shouldBe` ["ab", "c_"]
solution "abcdef" `shouldBe` ["ab", "cd", "ef"]

Find The Parity Outlier

You are given an array (which will have a length of at least 3, but could be very large) containing integers. The array is either entirely comprised of odd integers or entirely comprised of even integers except for a single integer N. Write a method that takes the array as an argument and returns this "outlier" N.

Examples

[2, 4, 0, 100, 4, 11, 2602, 36]
Should return: 11 (the only odd number)

[160, 3, 1719, 19, 11, 13, -21]
Should return: 160 (the only even number)

Detect Pangram

A pangram is a sentence that contains every single letter of the alphabet at least once. For example, the sentence The quick brown fox jumps over the lazy dog is a pangram, because it uses the letters A-Z at least once (case is irrelevant).

Given a string, detect whether or not it is a pangram. Return True if it is, False if not. Ignore numbers and punctuation.

Data Reverse

Description:

A stream of data is received and needs to be reversed. Each segment is 8 bits long, meaning the order of these segments need to be reversed, for example:

11111111  00000000  00001111  10101010
  byte1     byte2     byte3     byte4

should become:

10101010  00001111  00000000  11111111
  byte4     byte3     byte2     byte1

The total number of bits will always be a multiple of 8. The data is given in an array as such:

[1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,0,1,0,1,0,1,0]

Shortest Word

Description:

Simple, given a string of words, return the length of the shortest word(s).

String will never be empty and you do not need to account for different data types.

Count the smiley faces!

Given an array (arr) as an argument complete the function countSmileys that should return the total number of smiling faces.

Rules for a smiling face:

• Each smiley face must contain a valid pair of eyes. Eyes can be marked as : or ;
• A smiley face can have a nose but it does not have to. Valid characters for a nose are - or ~
• Every smiling face must have a smiling mouth that should be marked with either ) or D.
  No additional characters are allowed except for those mentioned.

Valid smiley face examples:

:) :D ;-D :~)

Invalid smiley faces:

;( :> :} :]

Example cases:

countSmileys([':)', ';(', ';}', ':-D']);       // should return 2;
countSmileys([';D', ':-(', ':-)', ';~)']);     // should return 3;
countSmileys([';]', ':[', ';*', ':$', ';-D']); // should return 1;

Note: In case of an empty array return 0. You will not be tested with invalid input (input will always be an array). Order of the face (eyes, nose, mouth) elements will always be the same

Find the missing letter

Write a method that takes an array of consecutive (increasing) letters as input and that returns the missing letter in the array.

You will always get an valid array. And it will be always exactly one letter be missing. The length of the array will always be at least 2.
The array will always contain letters in only one case.

Example:

['a','b','c','d','f'] -> 'e'
['O','Q','R','S'] -> 'P'

(Use the English alphabet with 26 letters!)