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<span id="Recursion"></span>While [[YBWC ]] is difficult to implement recursively, ABDADA is not. In YBWC, when a processor receives an evaluation answer from one of its slaves, it must be able to produce a jump in the search depth if this evaluation produces a pruning of the current master node. So the values of [[Alpha|alpha]] and [[Beta|beta]] must at least be kept in [[Array|arrays]] indexed by [[Ply|ply]] distance from root, and special arrangements must be made to counteract the disruption that might occur from confusing depths. Therefor YBWC needs a hugely modified [[Iterative Search|iterative search]] algorithm. In his paper <ref>[[Jean-Christophe Weill]] ('''1996'''). ''[http://portal.acm.org/citation.cfm?id=228345 The ABDADA Distributed Minimax Search Agorithm]''. Proceedings of the 1996 ACM Computer Science Conference, pp. 131-138. ACM, New York, N.Y, reprinted [[ICGA Journal#19_1|ICCA Journal, Vol. 19, No. 1]], [http://www.recherche.enac.fr/%7Eweill/publications/acm.ps.gz zipped postscript]</ref> , Weill states that using ABDADA within a recursive [[NegaScout]] framework was 30% faster than a none-recursive search, which was observed independently by [[Mark Brockington]] in 1994 <ref>[[Mark Brockington]] ('''1994'''). ''An Implementation of the Young Brothers Wait Concept''. Internal report, [[University of Alberta]]</ref> . It can be explained by the fact that within high-level languages and their compilers for certain target platforms, the use of procedure [[Stack|stacks]] is much more optimized than the use of indexed arrays, also observed by [https://en.wikipedia.org/wiki/Niklaus_Wirth Niklaus Wirth] concerning the [https://en.wikipedia.org/wiki/Quicksort Quicksort] algorithm <ref>[https://en.wikipedia.org/wiki/Niklaus_Wirth Niklaus Wirth] ('''1976'''). ''[https://en.wikipedia.org/wiki/Algorithms_%2B_Data_Structures_%3D_Programs Algorithms + Data Structures = Programs]''. pp 100</ref> .