Finding Repeats With Fixed Gap
Abstract
We propose an algorithm for finding in a word all pairs of occurrences of the same subword with a given distance r between them. The obtained complexity is O(n\log r +S), where S is the size of the output. We also show how the algorithm can be modified in order to find all such pairs of occurrences separated by a given word. The solution uses an algorithm for finding all quasi-squares in two strings, a problem that generalizes the known problem of searching for squares.