I have two lists with equal length, and I want to exchange the elements on every even positions. For example,
{{1, 2, 3, 4, 5}, {6, 7, 8, 9, 10}}
will return
{{1, 7, 3, 9, 5}, {6, 2, 8, 4, 10}}
It has to be able to deal with length of both even and odd; and in the real case the list is very long. I am not satisfied with naive approaches with indexing and partitioning because they are slow. Is there any fast approaches?