Approximation algorithm for the cyclic swap problem
Yoán José Pinzón Ardila, Costas S. Iliopoulos, Gad M. Landau, Manal Mohamed · Prague Stringology Conference · 2005
Given two n-bit (cyclic) binary strings, A and B, represented on a circle (necklace instances). Let each sequence have the same number k of 1’s. We are interested in computing the cyclic swap distance between A and B, i.e., the minimum number of swaps needed to convert A into B, minimized over all rotations of B. We show that this distance may be approximated in O(n + k2) time.