Hello mvkarthik,

I moved your post from Perl Monks Discussion to Seekers of Perl Wisdom. Please update your post by adding <code> ... </code> tags to make it readable. In addition, a small driver script together with sample input and desired output would go a long way to explaining what you are trying to accomplish.

From the node title, I gather you want to share a hash between recursive calls of the subroutine? You have:

sub get_lower_level_ehms_count()
{
    my %design_hash = %{ @_[0] };
    local %ehm_count;
    ...
[download]

but, after the first call, this makes a local copy of the hash, so it’s effectively the same as using my here. (See local.) Perhaps you want something like this?

{
    my %ehm_count;

    sub get_lower_level_ehms_count
    {
        ...
    }
}
[download]

A couple of other points:

1. In sub get_lower_level_ehms_count() {, the parentheses () are a prototype specifying that the sub takes no arguments. This is clearly not what you want, since you access the first element of @_ within the sub. If you remove the prototype, you can also remove the initial ampersand (&) from the recursive call: get_lower_level_ehms_count(\%ehm_hash);. See perlsub#Prototypes.

2. In the assignment my %design_hash = %{@_[0]};, @_[0] is actually an array slice. Since you are accessing only a single array element, this is better written as $_[0].

Hope that helps,