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From: Norbert Melzer <norbert.melzer@gmx.net>
Newsgroups: comp.lang.ruby
Subject: Re: Making a count of unique elements in an array
Date: Thu, 12 Dec 2013 19:44:47 +0100
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On 12.12.2013 18:56, vsingla160@gmail.com wrote:

> if i have to count no. of distinct elements in a 2D array ,then what
> to do??

I think at least one of this will do it:

```
[1] pry(main)> [[1,2],[2,3],[1,2]].count
=> 3
[2] pry(main)> [[1,2],[2,3],[1,2]].uniq
=> [[1, 2], [2, 3]]
[3] pry(main)> [[1,2],[2,3],[1,2]].uniq.count
=> 2
[4] pry(main)> [[1,2],[2,3],[1,2]].flatten
=> [1, 2, 2, 3, 1, 2]
[5] pry(main)> [[1,2],[2,3],[1,2]].flatten.uniq
=> [1, 2, 3]
[6] pry(main)> [[1,2],[2,3],[1,2]].flatten.uniq.count
=> 3
```

There is a very beautiful ressource:
<http://www.ruby-doc.org/core-2.0.0/Array.html>

You can find nearly anything about arrays there…

HTH
Norbert