Since my solutions are neither efficient nor concise, I wonder if someone could help me with the following problem. Suppose
(Just a short and simplified version - L is a huge list). I need the elements to be rearranged as follows
that is, the first sublist of newL contains the first elements of all sublists of L without , the second sublist of newL contains the second elements of all sublists of L without  and so on.
How can that be achieved without seq and remove?
PS. My solution
The size of the sublists does not change.