How do I count one characters as only one even though it is appears more than once?

Question

I'm trying to do a little logo guessing game. I have an array of logo names and then you have to guess which logo name it is.

I have removed the whitespaces from the logo names using the code below.

var cleanLogoName = randomLogoName.replace(/ /g,'');

Then I want to know the amount of characters in the logo name by using this code.

var numberOfChar = cleanLogoName.length;

The game however is a hangman game, so I won't need to count the same characters more than once.

For example:

Coca cola

I would only need to count the the c, a, o one time and not two times.

Is there anyway to do this with javaScript?

In your hangman game logic you surely have a list of single characters. Can't you just count that? Please show us your code. — Bergi, Aug 15 '13 at 12:37
Split your string to an array and then use something like this: http://stackoverflow.com/questions/1960473/unique-values-in-an-array — Alma Do, Aug 15 '13 at 12:38
I need to know the total of characters without duplicates to find out when someone has guessed the word. — user2559792, Aug 15 '13 at 12:41

score 4 · Accepted Answer · answered Aug 15 '13 at 12:39

4

You can use a regex to detect and remove characters that appear multiple times:

"coca cola".replace(/\s|(.)(?=.*\1)/g, "").length // 4

(using a backreference to a captured letter in a lookahead expression)

answered Aug 15 '13 at 12:39

Bergi

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Thank you so much, this looks promising. – user2559792 Aug 15 '13 at 12:44
If I replace "coca cola" with a variable name containing a string then I get an error? – user2559792 Aug 15 '13 at 12:52
Depends on the variable. What error is it? The `.replace` doesn't throw one. – Bergi Aug 15 '13 at 13:07
1

Sorry my bad, was passing the wrong variable that wasn't a string. Now it's working fantastic. Thank you very much. – user2559792 Aug 15 '13 at 13:18

score 1 · Answer 2 · answered Aug 15 '13 at 12:40

I think some pseudo code will help you understand the concept a little better, and encourage you to solve the problem yourself. And this offers a regex free solution, should you want it.

Define an empty list of characters.
Define a variable, count = 0;

for every letter in your word
    if(list does not contain this letter)
        count = count + 1
        list.add(count)

How do I count one characters as only one even though it is appears more than once?

2 Answers2