Efficient Implementation of Lazy Suffix Trees

Abstract

We present an efficient implementation of a write-only topdown construction for suffix trees. Our implementation is based on a new, space-efficient representation of suffix trees which requires only 12 bytes per input character in the worst case, and 8.5 bytes per input character on average for a collection of files of different type. We show how to efficiently implement the lazy evaluation of suffix trees such that a subtree is evaluated not before it is traversed for the first time. Our experiments show that for the problem of searching many exact patterns in a fixed input string, the lazy top-down construction is often faster and more space efficient than other methods.

Partially supported by DFG-grant Ku 1257/1-1.