Hello,

The Perl hast How-To may be of use. A hash of arrays would solve the problem of having a hash of priorities with multiple diseases each having the same priority. But, an array of arrays would as well.

What's in the database? Knowing how that data is presented might be helpful.

EDIT:

I think I might have a better idea of what you're looking for. You could try something like this:

#!/usr/bin/perl -w
use strict;

my @diseases = ();

$diseases[0] = ['flu','cold'];
$diseases[1] = ['Diabetics'];
$diseases[2] = ['Typhoid'];
$diseases[3] = ['Measels'];

for(my $priority = 0;$priority < scalar(@diseases);$priority++){
    print "Priority $priority diseases:\n";
    foreach(@{$diseases[$priority]}){
        print "\t$_\n";
    }
}
[download]

Priority 0 diseases:
        flu
        cold
Priority 1 diseases:
        Diabetics
Priority 2 diseases:
        Typhoid
Priority 3 diseases:
        Measels
[download]

EDIT #2: Just noticed; you need to add 1 to $priority when printing to make it display properly, since your priority list starts with '1' and not '0'.