Hello: You have to escape the '|' because is interpreted in the split as 'OR'.
Try this code to see what I say:

use strict;
my $a='hello|world';
my $c='|';
my @letras = split /$c/,$a;
for (@letras)    {
    print "[$_]";
}
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Change the third line to do the split:

my $c='\|';
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Hope this helps

Hopes

$_=$,=q,\,@4O,,s,^$,$\,,s,s,^,b9,s,
$_^=q,$\^-]!,,print
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