Extended suffix array construction using Lyndon factors

Abstract

In this paper, we are extending the novel approach of incremental suffix array construction using Lyndon factorization to the construction of extended suffix array where extended suffix array is the suffix array along with the corresponding longest common prefix (LCP) array. Main motive behind the incremental and simultaneous construction of suffix array and LCP array is that both involve in calculating the order information by considering the common prefixes of the suffixes. As local suffixes once sorted have the same sorted order when these are merged with sorted suffixes of another Lyndon factor. So, merging of Lyndon factors is simply merging of two sorted lists of suffixes of these Lyndon factors. Also, the two sorted orders coincide thus making the merging of Lyndon factors a simple merging of two sorted lists of suffixes. Incremental LCP construction simultaneously saves a lot of computation and hence time. The proposed approach has quadratic run time and the disk working space requirement is O(n). Experiments also show the performance gain of our approach in terms of time over the existing method of incremental construction.