MITSUBISHI ELECTRIC RESEARCH LABORATORIES http://www.merl.com Some Useful Lisp Algorithms: Part 1 Richard C. Waters TR91-04 December 1991 Abstract Richard C. Waters Chapter 3 Implementing¨ Queues in Lisp(co-authored¨ by P. Norvig) presents several different algorithms for implementing queues in Lisp. It discusses why the obvious list- based implementation of queues is inefficient and the particular situations where more complex implementations are appropriate. This work may not be copied or reproduced in whole or in part for any commercial purpose. Permission to copy in whole or in part without payment of fee is granted for nonprofit educational and research purposes provided that all such whole or partial copies include the following: a notice that such copying is by permission of Mitsubishi Electric Research Laboratories, Inc.; an acknowledgment of the authors and individual contributions to the work; and all applicable portions of the copyright notice. 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Copyright c Mitsubishi Electric Research Laboratories, Inc., 1991 201 Broadway, Cambridge, Massachusetts 02139 MERLCoverPageSide2 witsuishi iletri eserh vortories ehnil eport WIEHR hemeer ISD IWWI y ihrd gF ters estrt his tehnil report gthers together three ppers tht were written during IWWI nd sumitted for pulition in egw visp ointersF ih pper desries useful visp lgorithmF ghpter I upporting the egression esting of visp rogrms4 presents system lled rt tht mintins dtse of tests nd utomtilly runs them when requestedF his n tke lot of omputer timeD ut does not tke ny of the progrmmer9s timeF es resultD ny ugs found y running the tests|nd this is lot more ugs thn you might think|re essentilly found for freeF ghpter P hetermining the goverge of est uite4 presents system lled over tht n help ssess the overge of suite of test sesF hen suite of test ses for progrm is run in onjuntion with overD sttistis re kept on whih onditions in the ode for the progrm re exerised nd whih re notF fsed on 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