Let the hash take care of duplicate key removal: 
my %hash;
foreach my $i (0 .. $#num) {
    my $key = $num[$i];
    my $value = $address[$i];
    $hash{$key} = $value;
}
print "$_ => $hash{$_}\n" for keys %hash;

[download]
It's not clear to me from your problem description that this is correct, but I'll submit it as a "talking point".

In reply to Re: Problem regarding storing the values in Hash. by trammell
in thread Problem regarding storing the values in Hash. by perlsen

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