Exercises

Submitting Your Solutions

⍝ click to copy ─→
]get -u https://github.com/dyalog-training/2025-ListsWorkshop/raw/refs/heads/main/lists-of-words.dws

Set your workspace ID to list-solutions-[your name].dws and save the workspace on your system with )SAVE.
Save your workspace often!
Define functions in this workspace according to the specifications below.
When you are ready to submit, erase the words variable so that your workspace is smaller:
```
]expunge words
```
You can get the words variable at any time from the original workspace:
```
]get -u -o=words https://github.com/dyalog-training/2025-ListsWorkshop/raw/refs/heads/main/lists-of-words.dws
```
Send your workspace to the email address you were given.

Arguments and Results

Unless specified otherwise, all functions take a nested list of character vectors as right argument. All words in the right argument consist solely of characters in ⎕A.

All Count* functions should return a simple scalar numeric result.

Running Tests

The Tests.Run function takes a namespace of solution functions as its right argument and runs the test suite using those solutions. Your solution functions must be correctly named. You may define your solutions in # and run the tests with Tests.Run #, or using another namespace that you create.

The optional left argument to Tests.Run is a scalar Boolean flag that indicates whether or not to pause execution in the case that a test errors or fails.

CountA

Define a function CountA that returns the count of words that contain the letter "A".

      CountA 'A' 'WORD' 'AT' 'A' 'TIME'
3

CountGORS

Define a function CountGORS that returns the count of words that contain the letter "G" or the letter "S".

      CountGORS ,¨'G' 'S' 'GS'
3

CountGANDS

Define a function CountGANDS that returns the count of words that contain the letter "G" and the letter "S".

      CountGANDS ,¨'G' 'S' 'GS'
1

CountELL

Define a function CountELL that returns the count of words that contain the substring "ELL".

      CountELL 'ELLA' 'BALL' 'BEND' 'BELL' 'BELLY'
3

CountCON

Define a function CountCON that returns the count of words that begin with "CON".

      CountCON 'CONNOR' 'BACON' 'ANACONDA' 'CONVERT'
2

CountITY

Define a function CountITY that returns the count of words that end with "ITY".

      CountITY 'CITY' 'PITYING' 'TEST' 'ABILITY' 'DEITY'
3

CountSandwich

Define a function CountSandwich that returns the count of words in its right argument that begin and end with the same character.

      CountSandwich 'FIFE' 'PEEP' 'TOOT'
2

Substrings

Define a function Substrings that returns words from the right argument list that are substrings of the simple character vector left argument. For example, substrings of "CONSIDERATION" include "SIDE" and "RATIO".

      ]box on
Was OFF
      'CONSIDERATION' Substrings 'SIDE' 'RAT' 'RATIO' 'HAT' 'PATIO'
┌────┬───┬─────┐
│SIDE│RAT│RATIO│
└────┴───┴─────┘

LongestWords

Define a function LongestWords that returns a nested vector of character vectors that are the longest words in its right argument list.

      LongestWords 'JUST' 'FOR' 'THESE' 'FIVE' 'WORDS'
┌─────┬─────┐
│THESE│WORDS│
└─────┴─────┘

LengthDistribution

Define a function LengthDistribution that returns a two-column matrix. The first column contains integers between 1 and the length of the longest word in the right argument. The second column is the count of words in the right argument that have that length.

      LengthDistribution 'JUST' 'FOR' 'THESE' 'FIVE' 'WORDS'
1 0
2 0
3 1
4 2
5 2

LengthByLetter

Define a function LengthByLetter that returns a two-column matrix. The first column contains the letters A to Z. The second column contains the average length of words in the right argument list that begin with that letter.

      LengthByLetter 'JUST' 'FOR' 'THESE' 'FIVE' 'WORDS'
A 0
B 0
C 0
D 0
E 0
F 3.5
G 0
H 0
I 0
J 4
K 0
L 0
M 0
N 0
O 0
P 0
Q 0
R 0
S 0
T 5
U 0
V 0
W 5
X 0
Y 0
Z 0

CountPalindromes

Define a function CountPalindromes that counts the number of words that are identical when reversed.

      CountPalindromes 'REED' 'DEED' 'DOG' 'RACECAR'
2

CountAlphabetical

Define a function CountAlphabetical that counts how many words have their letters in alphabetical order.

      CountAlphabetical 'FEEL' 'ACER' 'SPOON' 'LOOPS' 'CENT'
3

CountRepeating

Define a function CountRepeating that counts how many words have consecutive repeated letters. For example, "deep" and "small" do but "special" does not.

      CountRepeating 'DEEP' 'SMALL' 'SPECIAL' 'BOB'
2

CountAlternating

Define a function CountAlternating that counts how many words have alternating vowels and consonants. For example, "solid" has alternating vowels and consonants, but "read" has two consecutive vowels and "angle" has three consecutive consonants. For this workshop, a vowel is defined as one of the characters "AEIOU".

      CountAlternating 'SOLID' 'READ' 'ANGLE'
1

Reverse

Define a function Reverse that reverses each word.

      Reverse 'SOLID' 'READ' 'ANGLE'
┌─────┬────┬─────┐
│DILOS│DAER│ELGNA│
└─────┴────┴─────┘

CountC_T

Define a function CountC_T that counts the number of words that contain the pattern C_T where _ is any single character.

      CountC_T 'CALLING' 'CUTTING' 'WALK' 'CAT' 'COT'
3

CountN_Q

Define a function CountN_Q that counts the number of words that contain the pattern N_Q where _ may be zero or more characters.

      CountN_Q 'ANTIQUE' 'QUININE'  'INEQUALITY' 'BANQUET' 'FISH'
3

RemoveVowels

Define a function RemoveVowels that returns the same words as its argument but with all vowels removed.

      RemoveVowels 'ALPHABETTY' 'SPAGHETTI'
┌───────┬──────┐
│LPHBTTY│SPGHTT│
└───────┴──────┘

RemoveInteriorVowels

Define a function RemoveVowels that returns the same words as its argument but with all interior vowels removed. An interior letter is a letter between, but not including, the first and last letter.

      RemoveInteriorVowels 'ALPHABETTY' 'SPAGHETTI'
┌────────┬───────┐
│ALPHBTTY│SPGHTTI│
└────────┴───────┘