(list 1 2 3 4)
(list 5 6 7 8)
result(list 1 5 2 6 3 7 4 8)
(list 5 6 7 8)
(list 1 2 3 4)
result(list 5 1 6 2 7 3 8 4)
(list 1 3 4)
(list 8 6 2 1)
result(list 1 8 3 6 4 2 1)
(list 1 3 4 8)
(list 2 5 7)
result(list 1 2 3 5 4 7 8)
(list)
(list 1 2 3)
result(list 1 2 3)