Optimal Parallel Searching an Array for Certain Repetitions

Repetitive substructures of two-dimensional arrays have been recently defined and studied in an attempt to parallel some of the analogous developments already known for strings. In the present paper we propose an O (log log n) time O(n3 log n) work optimally fast, optimal parallel CRCW-PRAM algorithm for detecting all repetitions of certain type in an n × n array.