1 research outputs found
On Sensitivity of Compact Directed Acyclic Word Graphs
Compact directed acyclic word graphs (CDAWGs) [Blumer et al. 1987] are a
fundamental data structure on strings with applications in text pattern
searching, data compression, and pattern discovery. Intuitively, the CDAWG of a
string is obtained by merging isomorphic subtrees of the suffix tree
[Weiner 1973] of the same string , thus CDAWGs are a compact indexing
structure. In this paper, we investigate the sensitivity of CDAWGs when a
single character edit operation (insertion, deletion, or substitution) is
performed at the left-end of the input string , namely, we are interested in
the worst-case increase in the size of the CDAWG after a left-end edit
operation. We prove that if is the number of edges of the CDAWG for string
, then the number of new edges added to the CDAWG after a left-end edit
operation on is less than . Further, we present almost matching lower
bounds on the sensitivity of CDAWGs for all cases of insertion, deletion, and
substitution.Comment: This is a full version of the paper accepted for WORDS 202