Sliding CDAWG perfection

Abstract

The Compact Directed Acyclic Word Graph (CDAWG) is a well-known suffix data structure designed for an efficient solution to problems on strings. Some applications, especially those from the data compression field, require maintaining a CDAWG over a sliding window. The fastest known solution to this problem is an approximation algorithm that slides a CDAWG in an amortized constant time. However, the existence of an exact algorithm performing within the same complexity bounds has been an open question so far. We show that the answer to this question is negative and present an on-line algorithm with the best asymptotic complexity possible. © 2009 Springer Berlin Heidelberg.