In another example (target molecule: XUKUURHRXDUEBC-KAYWLYCHSA-N, search depth of 3 reaction steps), the total number of substances of in-degree ¿ 1 is 51 and 42 for the +/-, and -/-configurations, respectively, after the second step of the SynGPS algorithm. Despite the +/-configuration containing only 25% more such substances, its processing time is twice longer than that of the -/-set, i.e. 149.9 sec vs. 73.6 sec . A more in -depth analysis of the relation between the processing time of enumeration step and the number of multi-in-degree nodes would be of interest, however, is beyond the scope of this study.