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Re: Delete slot in the middle of an array and shift remaining

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On 25 Nov 2011 10:39:52 GMT, Svenfischer2@email.com (Sven Fischer)
wrote, quoted or indirectly quoted someone who said :

>How can I do this most easily?
>Is this possible without iteration in a "while" loop?
 
The easy and standard way to do this is to use an ArrayList.  It has a
method to do this.  Arrays are for groups of elements where you do not
add or remove after initial creation. 
see http://mindprod.com/jgloss/arraylist.html

A slightly more hairy-chested way to do it is to use System.arraycopy
which is a native method that can take advantage of the hardware's
ability to move whacking hunks of bytes around at a time.
see http://mindprod.com/jgloss/array.html

To do it the Pascalan way you need a loop that maintains two indexes
from and to. They both increment/decrement each time around the loop.
If there is overlap, you must work either up or down to avoid
overwriting. see http://mindprod.com/jgloss/jcheat.html for hints on
how to do loops with two indexes. 

You can peek inside the ArrayList code to see how it handles inserting
and deleting. look inside src.zip.

This takes me back. I wrote various moves that  implemented this logic
for BBL Forth/Abundance.

-- 
Roedy Green Canadian Mind Products
http://mindprod.com
I can't come to bed just yet. Somebody is wrong on the Internet. 

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Delete slot in the middle of an array and shift remaining Svenfischer2@email.com (Sven Fischer) - 2011-11-25 10:39 +0000
  Re: Delete slot in the middle of an array and shift remaining Lew <lewbloch@gmail.com> - 2011-11-25 03:21 -0800
    Re: Delete slot in the middle of an array and shift remaining Magnus Warker <magnux@mailinator.com> - 2011-11-25 18:44 +0100
      Re: Delete slot in the middle of an array and shift remaining Lew <lewbloch@gmail.com> - 2011-11-25 09:55 -0800
        Re: Delete slot in the middle of an array and shift remaining Arne Vajhøj <arne@vajhoej.dk> - 2011-11-25 21:22 -0500
          Re: Delete slot in the middle of an array and shift remaining Sven Fischer <svenfischer2@email.com> - 2011-11-26 13:48 +0100
            Re: Delete slot in the middle of an array and shift remaining Gene Wirchenko <genew@ocis.net> - 2011-11-26 21:25 -0800
      Re: Delete slot in the middle of an array and shift remaining Patricia Shanahan <pats@acm.org> - 2011-11-25 10:17 -0800
        Re: Delete slot in the middle of an array and shift remaining markspace <-@.> - 2011-11-25 10:24 -0800
        Re: Delete slot in the middle of an array and shift remaining Lew <lewbloch@gmail.com> - 2011-11-25 11:26 -0800
          Re: Delete slot in the middle of an array and shift remaining Arne Vajhøj <arne@vajhoej.dk> - 2011-11-25 21:17 -0500
        Re: Delete slot in the middle of an array and shift remaining Roedy Green <see_website@mindprod.com.invalid> - 2011-11-25 14:15 -0800
  Re: Delete slot in the middle of an array and shift remaining Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-11-25 08:08 -0500
  Re: Delete slot in the middle of an array and shift remaining markspace <-@.> - 2011-11-25 07:39 -0800
  Re: Delete slot in the middle of an array and shift remaining Roedy Green <see_website@mindprod.com.invalid> - 2011-11-25 13:35 -0800
  Re: Delete slot in the middle of an array and shift remaining Arne Vajhøj <arne@vajhoej.dk> - 2011-11-25 21:16 -0500

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