An efficient way to remove an element from an array

sophate has asked for the wisdom of the Perl Monks concerning the following question:

Hi Monks,

pop and shift can remove an element from an array at the end or from the beginning. Is there any efficient way to remove an array element in the middle? I'm doing this with the codes below. But just wondering if there is any better way of doing this? ("delete" only sets the element to undef but doesn't remove it from the array)

#!/usr/bin/perl -w
use warnings;
use strict;

my @FullArray=qw(1 2 3 4 5 6);
print "The number of elements: [",scalar(@FullArray),"]\n";
my $LastElement = $#FullArray;
print "Removing the 3rd element . . .\n";
my @Temp = @FullArray[0..1];
@FullArray = (@Temp, @FullArray[3..$LastElement]);
print "The number of elements: [",scalar(@FullArray),"]\n";
print "The remaining elements:[@FullArray]\n";
[download]

Comment on An efficient way to remove an element from an array Download Code

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Re: An efficient way to remove an element from an array by Corion (Patriarch) on Aug 06, 2012 at 10:28 UTC
See splice. For understanding `splice` I really recommend reimplementing the `pop`, `push`, `shift` and `unshift` functions using only `splice`.	[reply] [d/l] [select]
Re^2: An efficient way to remove an element from an array by Anonymous Monk on Aug 06, 2012 at 10:32 UTC
The documentation kinda gives away the implementation :) literally :)	[reply]
Re^3: An efficient way to remove an element from an array by Corion (Patriarch) on Aug 06, 2012 at 10:35 UTC
Sure, but working through the why and how is still educative `:)`.	[reply] [d/l]
Re^2: An efficient way to remove an element from an array by sophate (Beadle) on Aug 06, 2012 at 10:34 UTC
Thanks. It's exactly what I'm looking for :)	[reply]
Re: An efficient way to remove an element from an array by AnomalousMonk (Archbishop) on Aug 06, 2012 at 19:10 UTC
Here's an 'efficient' method if you're completely unconcerned about maintaining array order. (This was published by someone else recently in response to a strikingly similar question.) `>perl -wMstrict -le "my @ra = (0, 1, 2, 3, 4, 5); print qq{@ra}; for my $i (2, 0, -2, -1) { $ra[$i] = $ra[-1]; --$#ra; print qq{removed element at index $i: @ra}; } " 0 1 2 3 4 5 removed element at index 2: 0 1 5 3 4 removed element at index 0: 4 1 5 3 removed element at index -2: 4 1 3 removed element at index -1: 4 1` [download]	[reply] [d/l]
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