W String

Kira likes to play with strings very much. Moreover he likes the shape of 'W' very much. He takes a string and try to make a 'W' shape out of it such that each angular point is a '#' character and each sides has same characters. He calls them W strings. For example, the W string can be formed from "aaaaa#bb#cc#dddd" such as: a a d a # d a b c d a b c d # # He also call the strings which can gen