At any given level, keys (as in my $n = keys %{ $hashref };) will tell you how many elements exist at that level.

Which if the only keys in the hash were the numeric ones, then that would tell you what number to use for the next insertion. But in that case, you'd be far better off using an array rather than a hash.

But for the second level in your structure, where you have other, non-numeric keys, then that won't work. But then, if you added a key '2' at that level, where are you going to store the associated 'name' & 'that'? Because if you try to store them as you have the first set, you'll just overwrite them.

Bottom line is that you almost certainly need to review your data structure.

Perhaps if you outlined what the data was and where it came from, we might be able to help you with that.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: Determine largest key in hash by BrowserUk
in thread Determine largest key in hash by Anonymous Monk

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