my $in=join (", ", (map { $_ = "'$_'" } @one));

 $sql="SELECT * FROM sistema WHERE codigo_inscripcion IN ($in) and mat
+ricula='$matricula'";
 $pdbh=$dbh->prepare($sql);
    $pdbh->execute();

# stuff here!
while (my $ref = $pdbh->fetchrow_hashref()) {

        if($ref->{'mon'} != ''){$mon="Mon$ref->{'mon'})}
        if($ref->{'tue'} != ''){$mar="Tue$ref->{'tue'}"}
        if($ref->{'wed'} != ''){$mie="Wed$ref->{'wed'}"}
        if($ref->{'thu'} != ''){$jue="Thu$ref->{'thu'}"}
        if($ref->{'fri'} != ''){$vie="Fri$ref->{'fri'}"}
        if($ref->{'sat'} != ''){$sab="Sat$ref->{'sat'}"}
        if($ref->{'sun'} != ''){$dom="Sun$ref->{'sun'}"}
}

$pdbh->finish();
exit;

if ($mon ne ''){
$lun=~ /([A-Za-z]*)([0-9]*)\/([0-9]*)/;

for($z=$2;$z<$3;$z++) { push (@soft, "$1$z"); } 
push (@soft, "$1$3");

print @soft;
exit;
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You might want to start with

use strict;
use warnings;
use diagnostics;
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and see what happens - I can see at least one typo that is causing you problems.

rdfield

You could change the while loop to something like:

my %seen;
while (my $ref = $pdbh->fetchrow_hashref()) {
    for (qw(mon tue wed thu fri sat sun)) {
       my $result = lcfirst($_).$ref->{$_} if $ref->{$_};
       if ($seen{$result}++) {
           warn "$seen found already";
       }
       else {
           push @results,$result;
       }
    }
}
print join("\n",@results);
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That should print out the results with duplicates removed in the format you seem to want.

-- 
Joost       downtime n. The period during which a system
            is error-free and immune from user input.
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