Re^3: Selective printing of the Duplicates


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Re^3: Selective printing of the Duplicates

by baxy77bax (Deacon)

on Jan 30, 2013 at 18:27 UTC ( [id://1016131]=note: print w/replies, xml )

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in reply to Re^2: Selective printing of the Duplicates
in thread Selective printing of the Duplicates

Now is it the last one or the second one. Are these duplicates or multiplicities??

So, given that these are repeated several times and you need the second one I would use :

my %seen = ();
my $tmp

...
$seen{$_}++;
if ($_ ne $tmp && $seen{$tmp} == 1){
  print $_;
  $tmp =$_;
}elsif ($_ eq $tmp){
  print $_ if $seen{$_} == 2;
}
[download]

however if it is the last one then:


my %seen = ();
my $tmp;
my $id;
...
if ($_ ne $tmp){
$seen{$tmp}=$id++;
}
and then in the second loop:


print $_ foreach (sort{$seen{$a}<=>$seen{$b}}keys %seen);
[download]

baxy