List::Util does come with Perl.

Thanks for isolating the problem. I was explaining it here while you were writing your post.

The only thing I didn't cover is that references evaluate to the address of the referenced item when they are treated as a number.

In reply to Re^3: 2d Array - making an array for the column then adding the values by ikegami
in thread 2d Array - making an array for the column then adding the values by hansoffate

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