using the last index ($#) requireds an array.
($#{$cacheHOA{$sum}} is trying to use it on a scalar, not an array. This is untested, but maybe ($#{@{$cacheHOA{$sum}}} would work.

Update Well,I'll be damned.

In reply to dereference the array ref by boo_radley
in thread Stumped on an array ref error... by Madams

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