From: Mike Stok <mike@...>
Date: 2008-11-12T08:03:46+09:00
Subject: Re: Advanced arrays


On Nov 11, 2008, at 5:29 PM, Stuart Clarke wrote:

> Hi all,
>
> I have a quick brain teaser. I  have an array full of data broken down
> into indivdual entries. I running a simple if statement to check for  
> an
> entry in the array, if my if statement finds that entry its prints out
> that entry. I want to add an extra step into this so, when my if
> statement finds an entry, I want it to look at the next entry and  
> check
> for something else, if it finds that, I want to look at the next entry
> and check for something else, if it finds all of the three entries  
> in a
> row, it prints out "You have found what you want"
>
> Any ideas?


It might be a case where Enumerable.each_cons will do what you want.   
Not knowing the size of the data set, and not having benchmarked it,  
this does seem to work:

#!/usr/bin/env ruby

def search_array(array, look_for)
   array.each_cons(look_for.length) do |chunk|
     if chunk == look_for
       puts "You have found what you want"
       return
     end
   end
   puts "no luck..."
end

sample = ('a' .. 'z').to_a
search_array(sample, ['l', 'm', 'n'])
search_array(sample, ['l', 'p', 'n'])

Hope this helps,

Mike

-- 

Mike Stok <mike@stok.ca>
http://www.stok.ca/~mike/

The "`Stok' disclaimers" apply.