19th Annual Symposium on Foundations of Computer Science (sfcs 1978)最新文献

{"title":"Should tables be sorted?","authors":"A. Yao","doi":"10.1145/322261.322274","DOIUrl":"https://doi.org/10.1145/322261.322274","url":null,"abstract":"We examine optimality questions in the following information retrieval problem: Given a set S of n keys, store them so that queries of the form \"Is x $in$ S?\" can be answered quickly. It is shown that, in a rather general model including al1 the commonly-used schemes, $lceil$ lg(n+l) $rceil$ probes to the table are needed in the worst case, provided the key space is sufficiently large. The effects of smaller key space and arbitrary encoding are also explored.","PeriodicalId":346837,"journal":{"name":"19th Annual Symposium on Foundations of Computer Science (sfcs 1978)","volume":"173 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1981-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116330755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Complexity of solvable cases of the decision problem for the predicate calculus","authors":"H. R. Lewis","doi":"10.1109/SFCS.1978.9","DOIUrl":"https://doi.org/10.1109/SFCS.1978.9","url":null,"abstract":"We analyze the computational complexity of determining whether F is satisfiable when F is a formula of the classical predicate calculus which obeys certain syntactic restrictions. For example, for the monadic predicate calculus and the Gödel or ∃ ... ∃∀∀∃ ... ∃ prefix class we obtain lower and upper nondeterministic time bounds of the form cn/log n. The main tool in in these proofs is a finite version of Wang's domino problem, about which we present an interesting open question.","PeriodicalId":346837,"journal":{"name":"19th Annual Symposium on Foundations of Computer Science (sfcs 1978)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1978-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124757641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A dichromatic framework for balanced trees","authors":"L. Guibas, R. Sedgewick","doi":"10.1109/SFCS.1978.3","DOIUrl":"https://doi.org/10.1109/SFCS.1978.3","url":null,"abstract":"In this paper we present a uniform framework for the implementation and study of balanced tree algorithms. We show how to imbed in this framework the best known balanced tree techniques and then use the framework to develop new algorithms which perform the update and rebalancing in one pass, on the way down towards a leaf. We conclude with a study of performance issues and concurrent updating.","PeriodicalId":346837,"journal":{"name":"19th Annual Symposium on Foundations of Computer Science (sfcs 1978)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1978-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121163884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On tape Bounded probabilistic turing machine transducers","authors":"Janos Simon, John Gill, James Hunt","doi":"10.1109/SFCS.1978.27","DOIUrl":"https://doi.org/10.1109/SFCS.1978.27","url":null,"abstract":"The tape requirements of probabilistic and deterministic Turing machine transducers are polynomially related.","PeriodicalId":346837,"journal":{"name":"19th Annual Symposium on Foundations of Computer Science (sfcs 1978)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1978-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114240149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lower bounds on information transfer in distributed computations","authors":"H. Abelson","doi":"10.1145/322186.322200","DOIUrl":"https://doi.org/10.1145/322186.322200","url":null,"abstract":"We derive a lower bound on the interprocessor information transfer required for computing a function in a distributed network configuration. The bound is expressed in terms of the function's derivatives, and we use it to exhibit functions whose computation requires a great deal of interprocess communication. As a sample application, we give lower bounds on information transfer in the distributed computation of some typical matrix operations. Traditional measures of computational complexity, such as the number of primitive operations or memory cells required to compute functions, do not form an adequate framework for assessing the complexity of computations carried out in distributed networks. Even in the relatively straightforward situation of memoryless processors arranged in highly structured configurations, Gentleman [4] has demonstrated that data movement, rather than arithmetic operations, can often be the significant factor in the performance of parallel computations. And for the more general kinds of distributed processing, involving arbitrary network configurations and distributed data bases, the situation is correspondingly more complex. This paper addresses the problem of measuring computational complexity in terms of the interprocess communication required when a computation is distributed among a number of processors. More precisely, we model the distributed computation of functions which depend upon large amounts of data by assuming that the data is partitioned into disjoint subsets, and that a processor is assigned to each subset. Each processor (which we can think of as a node in a computational network) computes some values based on its own \"local\" data, and transmits these values to other processors, which are able to use them in subsequent local comutations. This \"compute locally and share information\" procedure is repeated over and over until finally some (predetermined) processor outputs the value of the desired function. In measuring the complexity of such computations we will be concerned, not with the individual local computations, but rather with the total information transfer, i.e., the total number of values which must be transmitted between processors. We derive a lower bound on the total information transfer required for computing a function in a distributed network. The bound is expressed in terms of the function's derivatives, and we use it to exhibit functions whose computation requires a great deal of interprocess communicaion. As a sample application, we give lower bounds on information transfer in the distributed computation of some typical matrix operations.","PeriodicalId":346837,"journal":{"name":"19th Annual Symposium on Foundations of Computer Science (sfcs 1978)","volume":"21 Suppl 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1978-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120953743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the power of the compass (or, why mazes are easier to search than graphs)","authors":"M. Blum, D. Kozen","doi":"10.1109/SFCS.1978.30","DOIUrl":"https://doi.org/10.1109/SFCS.1978.30","url":null,"abstract":"About the same time, A.N. Shah gave a finite autom~ton with 5 pebbles which could search an arbitrary maze (the autonlaton may drop a pebble on a cell it is visiting, then upon returning to that cell later on can sense the pebble's presence, and if desired pick it up and move it to a new cell). Shah also conjectured that fewer than 5 pebbles would not suffice. The first of our two main results is that, contrary to Shah's conjecture, the search can be implemented with just two pebbles. The question is still open whether a finite automaton with just one pebble can search any maze.","PeriodicalId":346837,"journal":{"name":"19th Annual Symposium on Foundations of Computer Science (sfcs 1978)","volume":"110 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1978-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121199891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Two theorems on random polynomial time","authors":"L. Adleman","doi":"10.1109/SFCS.1978.37","DOIUrl":"https://doi.org/10.1109/SFCS.1978.37","url":null,"abstract":"The use of randomness in computation was first studied in abstraction by Gill [4]. In recent years its use in both practical and theoretical areas has become apparent. Strassen and Solovay [10]; Miller [7]; and Rabin [8] have used it to transform primality testing into a (for many purposes) tractible problem. We can see in retrospect that it was implicit in algorithms by Ber1ekamp [2], Lehmer [6], and Cippola [3] (1903!). Where the traditional method of polynomial reduction has been inapplicable, randomness has been used in demonstrating intractibility by Adleman and Manders [1], and in showing problems equivalent by Rabin [9]. In light of these developments and the insights they provide, a new examination of randomness is in order.","PeriodicalId":346837,"journal":{"name":"19th Annual Symposium on Foundations of Computer Science (sfcs 1978)","volume":"187 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1978-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116660817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"GO is pspace hard","authors":"David Lichtenstein, M. Sipser","doi":"10.1109/SFCS.1978.17","DOIUrl":"https://doi.org/10.1109/SFCS.1978.17","url":null,"abstract":"A great deal of effort has been spent in the search for optimal and computationally feasible game strategies. In some cases (e.g. Bridge-it, Nim), such strategies have been found, vhile in others the search has been unsuccessful. Recently, it has become possible to provide compelling evidence that such strategies may not always exist. Even and Tarjan [1] and Schaefer [2] have shown that determining which player has a winning strategy in certain combinatorial games is a polynomial space complete problem [3]. (See also [4;5].)","PeriodicalId":346837,"journal":{"name":"19th Annual Symposium on Foundations of Computer Science (sfcs 1978)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1978-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131764769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On lifted problems","authors":"C. Yap","doi":"10.1109/SFCS.1978.25","DOIUrl":"https://doi.org/10.1109/SFCS.1978.25","url":null,"abstract":"This study may be viewed from the more general context of a theory of computational problems. An environment E= 〈L,D〉 consists of a class of structures D and a language L for D. A problem in E is a pair of sets of formulas P = 〈Π|Γ〉, with problem predicate Π. Let Ereal = 〈Lreal,{R}〉 and Elin = 〈Llin,Dlin〉 where R are the reals, Dlin is the class of totally ordered structures, Lreal and Llin are the languages of real ordered fields and linear orders, respectively. A problem P = 〈Π|Γ〉 in Ereal is a lifted problem (from Elin) if Π ε Llin. The following interpretes an informal conjecture of Yao: CONJECTURE: Binary comparisons can solve nonredundant, full, lifted problems in Ereal as efficiently as general linear comparisons. The conjecture remains open. We may attack the conjecture by eliminating those comparisons that do not help or by studying those subclass of problems that are not helped by general linear comparisons. Various partial results are obtained, corresponding to these two approaches.","PeriodicalId":346837,"journal":{"name":"19th Annual Symposium on Foundations of Computer Science (sfcs 1978)","volume":"130 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1978-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122761606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Description and analysis of an efficient priority queue representation","authors":"J. Françon, G. Viennot, J. Vuillemin","doi":"10.1109/SFCS.1978.13","DOIUrl":"https://doi.org/10.1109/SFCS.1978.13","url":null,"abstract":"We present a new data-structure for representing priority queues, the pagoda. A detailed analysis shows that the pagoda provides a very efficient implementation of priority queues, where our measure of efficiency is the average run time of the various algorithms. It handles an arbitrary sequence of n primitive operations chosen from MIN, INSERT, UNION, EXTRACT and EXTRACTMIN in time o(n log n). The constant factors affecting these asymptotic run time are small enough to make the pagoda competitive with any other priority queue, including structures which cannot handle UNION or EXTRACT. The given algorithms process an arbitrary sequence of n operations MIN, INSERT and EXTRACT in linear average time O(n), and a sequence of n INSERT in linear worst case time O(n).","PeriodicalId":346837,"journal":{"name":"19th Annual Symposium on Foundations of Computer Science (sfcs 1978)","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1978-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126168689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}