A note on efficient computation of all Abelian periods in a string

We derive a simple efficient algorithm for Abelian periods knowing all Abelian squares in a string. An efficient algorithm for the latter problem was given by Cummings and Smyth in 1997. By the way we show an alternative algorithm for Abelian squares. We also obtain a linear time algorithm finding all “long” Abelian periods. The aim of the paper is a (new) reduction of the problem of all Abelian periods to that of (already solved) all Abelian squares which provides new insight into both connected problems.

► We show a reduction of the Abelian periods problem to Abelian squares in a string.
► We derive a simple O(n2)O(n2) time algorithm for Abelian periods.
► We obtain a linear time algorithm finding all long Abelian periods.