  We study a variation of the classical Shortest Common Superstring (SCS)
problem in which a shortest superstring of a finite set of strings $S$ is
sought containing as a factor every string of $S$ or its reversal. We call this
problem Shortest Common Superstring with Reversals (SCS-R). This problem has
been introduced by Jiang et al., who designed a greedy-like algorithm with
length approximation ratio $4$. In this paper, we show that a natural
adaptation of the classical greedy algorithm for SCS has (optimal) compression
ratio $\frac12$, i.e., the sum of the overlaps in the output string is at least
half the sum of the overlaps in an optimal solution. We also provide a
linear-time implementation of our algorithm.
