From: "Olivier D." <nkh@...2_nospam.fr>
Date: 2004-08-17T14:41:05+09:00
Subject: Re: Q: Shifting a hash anf and array

On 2004-08-17, Meino Christian Cramer <Meino.Cramer@gmx.de> wrote:
>  Contents of the array before the trick:
>
>  1 2 3 4 5 6 7 8 9 0        index
>  A B C D E F G H I J		contents
>
>  Contents of the array after the trick:
>
>  1 2 3 4 5 6 7 8 9 0        index
>  J A B C D E F G H I		contents

I used my algorithm skills to come up with this strange solution:
swap every consecutive values starting from the beginning of the array,
which can be written with the methods:

class Array
  def left_shift!
    each_index do |i|
	  self[i], self[i+1] = self[i+1], self[i] if self[i+1]
	end
  end

  # of course you can prefer the cleaner:
  def left_shift_v2!
    obj = shift
	self << obj
  end

  def right_shift!
    obj = pop
	unshift obj
  end
end

-- 
Olivier D.