Strings of strings are strings made of strings. Being a master string stringer such as your stringy self, Ran the cat needs your help to string together a string of strings, so that he'll have a fun string of strings to play with. To make a string of strings a fun string of strings though, the strings have to be strung together in particular ways.
One way to do this is to take two strings, cut them up, and put them together. Given two strings, A and B, cut them up into pieces of length n. Then join these pieces together in an alternating manner. The lengths of the strings will be the same, and will be multiples of n.
Two strings, A and B.
Followed by an integer, n
The strung string of strings.
For 30% of the allocated score, length of A ≤ 1000
For 100% of the allocated score, length of A ≤ 1000000