Hi all, I am new to hash references so I am not too familiar with all of the related basics.

I have made a hash or arrays HoCl. For each Cluster_num there is a list of members. I want to find for each pair of members how many of the same clusters they belong to $overlap. The script is working as expected (before I added the line about 0). But i want the overlap value to be 0 as a default. How do I set the default value for overlap? Thank you 

my $overlap = {};
foreach $Cluster_Num (keys %HoCl){
        my @members=@{$HoCl{$Cluster_Num}};
        my $count = scalar(@members);
        for (my $i=0;$i<$count;$i++){
                for (my $j=$i+1;$j<$count;$j++) {
                $overlap -> {$members[$i]} -> {$members[$j]} = 0;
                $overlap -> {$members[$i]} -> {$members[$j]} ++;
                $overlap -> {$members[$j]} -> {$members[$i]} ++;
}
}
}

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In reply to how to set a value for a hash reference by AWallBuilder

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