Counting 5-letter words

Over at the MiniScript community a "daily MiniScript challenge" has been announced.

It consists of small exercises to try on MiniScript / Mini Micro.

For a while I have been wanting to write blog posts about Mini Micro - so I take this as an opportunity not only to solve the challenges (the easy part) but to write a blog post about it!

So, let's begin ...

The first challenge is called:

How many 5-letter words are there?

The first challenge is easy: from a given list of words, count how many 5-letter words there are.

The list of words can be found on Mini Micro under:

/sys/data/englishWords.txt

How do we solve this?

We need to:

1) Open the file
2) Iterate over each line
3) Determine the line's length
4) Increase a counter if the length is 5
5) Print the result

A file is opened with file.open. It returns a FileHandle object.

In turn, we can ask the FileHandle to read a line (with readLine) and also if we are at the end of the file (with atEnd).

Let's try that:

] wordsFile = file.open("/sys/data/englishWords.txt")
] wordsFile.atEnd
0

Let's read a some lines:

] wordsFile.readLine
a
] wordsFile.readLine
aah
] wordsFile.readLine
aardvark
] wordsFile.readLine
aardvarks
] wordsFile.readLine
abaci
] wordsFile.readLine
aback

We see it works. With this we have the necessary elements iterate over all lines.

Over at the editor we could type something like this:

wordsFile = file.open("/sys/data/englishWords.txt")
while not wordsFile.atEnd
    word = wordsFile.readLine
    print word
end while

Note how we are iterating in a loop while the file is not at the end. Don't forget the not operator.

This will print all words contained in the file ... but they are a lot! After some seconds I interrupted the program with CTRL-C

We could instead count the amount of lines. Let's do that instead:

count = 0

wordsFile = file.open("/sys/data/englishWords.txt")

while not wordsFile.atEnd
    word = wordsFile.readLine
    count = count + 1
end while

print "The file contains " + count + " words"

Now, this was much faster. My result was:

The file contains 64664 words

Yours? Should be the same. Unless the list got updated.

This program is now very close to what we wanted to achieve: count only the words that are 5 letters long.

In order to measure a string's length we use the intrinsic function len, which works on lists, maps and strings.

The program then needs only a small change. Instead of just always counting each line:

count = count + 1

... we will do so conditionally. Change the line above for:

if len(word) == 5 then count = count + 1

This can be written in one line as above or alternatively as:

if len(word) == 5 then 
    count = count + 1
end if

It would be also appropriate to change the result-message. Something like this would do:

print "There are " + count + " 5-letter words"

Try the program now. What happens when you run it?

I get:

Did you also get that?

This is the end version of my program:

Hope this mini-challenge was fun and you learnt some MiniScript / MiniMicro.

See you in the next one!

Comments

[JoeStrout]

Great post! And don't forget, an alternative to using file.open, f.atEnd, and f.readLine is to use file.readLines, which loads the whole file into a list you can easily iterate over.

[Sebastian Nozzi]

Thanks! Did not know that :-)

For completeness' sake, here is the program with the for-loop / readLines variant:

Note how a file-handle is not returned. Instead a list of all lines in the files in returned directly.

It can then be directly iterated with for [variable] in [collection], where collection in this case is a list (but could have been a string or a map).