#!/usr/bin/perl
use 5.014;

my @matches;
my @arr = qw/a1 ab2 aab3 ac4 dc5 bc6 da7 cb8 dbca9 aa0/;

for $_( @arr ) {
    if ($_ =~ m/a/g) {
        say "\t regex matches $_";
        push @matches, $_;
    }
}

for my $match( @matches) {
    say $match;
}