从数组中删除原始元素而不删除其在 perl 中的重复项

Question

I have an array with duplicate elements. I would like to remove one element at a time without iterating in a loop. Also, if I remove an element, if any duplicate element exists for that element it should remain in the array. Is there any way to do this in perl?

Answer 1

One loop to store elements in hash, and one grep to show remaining elements. All this assuming that undef is not occurring as value in your array of duplicates.

use strict;
use warnings;
use Data::Dumper;

my @r = (1..8, 1..8);

my %ref;
push @{ $ref{$_} }, \$_ for @r;

my $to_remove = 2;
undef ${shift @{ $ref{$to_remove} }};
print Dumper \@r;

undef ${shift @{ $ref{$to_remove} }};
print Dumper \@r;

print Dumper [ grep defined, @r ];