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55
An Incremental Algorithm for a Generalization of the ShortestPath Problem
, 1992
"... The grammar problem, a generalization of the singlesource shortestpath problem introduced by Knuth, is to compute the minimumcost derivation of a terminal string from each nonterminal of a given contextfree grammar, with the cost of a derivation being suitably defined. This problem also subsume ..."
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Cited by 116 (1 self)
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The grammar problem, a generalization of the singlesource shortestpath problem introduced by Knuth, is to compute the minimumcost derivation of a terminal string from each nonterminal of a given contextfree grammar, with the cost of a derivation being suitably defined. This problem also subsumes the problem of finding optimal hyperpaths in directed hypergraphs (under varying optimization criteria) that has received attention recently. In this paper we present an incremental algorithm for a version of the grammar problem. As a special case of this algorithm we obtain an efficient incremental algorithm for the singlesource shortestpath problem with positive edge lengths. The aspect of our work that distinguishes it from other work on the dynamic shortestpath problem is its ability to handle "multiple heterogeneous modifications": between updates, the input graph is allowed to be restructured by an arbitrary mixture of edge insertions, edge deletions, and edgelength changes.
On the Computational Complexity of Dynamic Graph Problems
 THEORETICAL COMPUTER SCIENCE
, 1996
"... ..."
An Incremental Algorithm for Satisfying Hierarchies of Multiway, Dataflow Constraints
 ACM Transactions on Programming Languages and Systems
, 1995
"... Oneway dataflow constraints have gained popularity in many types of interactive systems because of their simplicity, efficiency, and manageability. Although it is widely acknowledged that multiway dataflow constraints could make it easier to specify certain relationships in these applications, con ..."
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Cited by 46 (1 self)
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Oneway dataflow constraints have gained popularity in many types of interactive systems because of their simplicity, efficiency, and manageability. Although it is widely acknowledged that multiway dataflow constraints could make it easier to specify certain relationships in these applications, concerns about their predictability and efficiency have impeded their acceptance. Constraint hierarchies have been developed to address the predictability problem and incremental algorithms have been developed to address the efficiency problem. However, existing incremental algorithms for satisfying constraint hierarchies encounter two difficulties: (1) they are incapable of guaranteeing an acyclic solution if a constraint hierarchy has one or more cyclic solutions, and (2) they require worstcase exponential time to satisfy systems of multioutput constraints. This paper surmounts these difficulties by presenting an 2 incremental algorithm called QuickPlan that satisfies in worst case O(N ) ...
A ConstraintBased Architecture for Local Search
 In OOPLSA’02
, 2002
"... Combinatorial optimization problems are ubiquitous in many practical applications. Yet most of them are challenging, both from computational complexity and programming standpoints. ..."
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Cited by 39 (15 self)
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Combinatorial optimization problems are ubiquitous in many practical applications. Yet most of them are challenging, both from computational complexity and programming standpoints.
Deriving incremental programs
, 1993
"... A systematic approach i s g i v en for deriving incremental programs from nonincremental programs written in a standard functional programming language. We exploit a number of program analysis and transformation techniques and domainspeci c knowledge, centered around e ective utilization of cachin ..."
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Cited by 39 (21 self)
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A systematic approach i s g i v en for deriving incremental programs from nonincremental programs written in a standard functional programming language. We exploit a number of program analysis and transformation techniques and domainspeci c knowledge, centered around e ective utilization of caching, in order to provide a degree of incrementality not otherwise achievable by a generic incremental evaluator. 1
Incremental Model Checking in the Modal MuCalculus
 IN CAV, VOLUME 818 OF LNCS
, 1994
"... We present an incremental algorithm for model checking in the alternation free fragment of the modal mucalculus, the first incremental algorithm for model checking of which we are aware. The basis for our algorithm, which we call MCI (for Model Checking Incrementally), is a lineartime algorithm d ..."
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Cited by 36 (2 self)
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We present an incremental algorithm for model checking in the alternation free fragment of the modal mucalculus, the first incremental algorithm for model checking of which we are aware. The basis for our algorithm, which we call MCI (for Model Checking Incrementally), is a lineartime algorithm due to Cleaveland and Steffen that performs global (nonincremental) computation of fixed points. MCI takes as input a set \Delta of changes to the labeled transition system under investigation, where a change constitutes an inserted or deleted transition; with virtually no additional cost, inserted and deleted states can also be accommodated. Like the CleavelandSteffen algorithm, MCI requires time linear in the size of the LTS in the worst case, but only time linear in \Delta in the best case. We give several examples to illustrate MCI in action, and discuss its implementation in the Concurrency Factory, an interactive design environment for concurrent systems.
ONLINE PLANARITY TESTING
, 1996
"... The online planaritytesting problem consists of performing the following operations on a planar graph G: (i) testing if a new edge can be added to G so that the resulting graph is itself planar; (ii) adding vertices and edges such that planarity is preserved. An efficient technique for online plan ..."
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Cited by 26 (2 self)
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The online planaritytesting problem consists of performing the following operations on a planar graph G: (i) testing if a new edge can be added to G so that the resulting graph is itself planar; (ii) adding vertices and edges such that planarity is preserved. An efficient technique for online planarity testing of a graph is presented that uses O(n) space and supports tests and insertions of vertices and edges in O(log n) time, where n is the current number of vertices of G. The bounds for tests and vertex insertions are worstcase and the bound for edge insertions is amortized. We also present other applications of this technique to dynamic algorithms for planar graphs.
Discovering auxiliary information for incremental computation
 In Symp. on Princ. of Prog. Lang
, 1996
"... This paper presents program analyses and transformations that discover a general class of auxiliary information for any incremental computation problem. Combining these techniques with previous techniques for caching intermediate results, we obtain a systematic approach that transforms nonincrementa ..."
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Cited by 22 (12 self)
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This paper presents program analyses and transformations that discover a general class of auxiliary information for any incremental computation problem. Combining these techniques with previous techniques for caching intermediate results, we obtain a systematic approach that transforms nonincremental programs into e cient incremental programs that use and maintain useful auxiliary information as well as useful intermediate results. The use of auxiliary information allows us to achieve a greater degree of incrementality than otherwise possible. Applications of the approach i nclude strength reduction in optimizing compilers and nite di erencing in transformational programming. 1
Online cycle detection and difference propagation for pointer analysis
 In Proceedings of the 3rd International Workshop on Source Code Analysis and Manipulation
, 2003
"... This paper presents and evaluates a number of techniques to improve the execution time of interprocedural pointer analysis in the context of large C programs. The analysis is formulated as a graph of set constraints and solved using a worklist algorithm. Indirections lead to new constraints being ad ..."
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Cited by 21 (3 self)
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This paper presents and evaluates a number of techniques to improve the execution time of interprocedural pointer analysis in the context of large C programs. The analysis is formulated as a graph of set constraints and solved using a worklist algorithm. Indirections lead to new constraints being added during this process. In this work, we present a new algorithm for online cycle detection, and a difference propagation technique which records changes in a variable’s solution. Effectiveness of these and other methods are evaluated experimentally using nine common ‘C ’ programs ranging between 1000 to 55000 lines of code. 1
Experimental Analysis of Dynamic Algorithms for the Single Source Shortest Path Problem
 ACM Jounal of Experimental Algorithmics
, 1997
"... In this paper we propose the first experimental study of the fully dynamic single source shortest paths problem on directed graphs with positive real edge weights. In particular, we perform an experimental analysis of three different algorithms: Dijkstra's algorithm, and the two output bounded al ..."
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Cited by 19 (2 self)
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In this paper we propose the first experimental study of the fully dynamic single source shortest paths problem on directed graphs with positive real edge weights. In particular, we perform an experimental analysis of three different algorithms: Dijkstra's algorithm, and the two output bounded algorithms proposed by Ramalingam and Reps in [31] and by Frigioni, MarchettiSpaccamela and Nanni in [18], respectively. The main goal of this paper is to provide a first experimental evidence for: (a) the effectiveness of dynamic algorithms for shortest paths with respect to a traditional static approach to this problem; (b) the validity of the theoretical model of output boundedness to analyze dynamic graph algorithms. Beside random generated graphs, useful to capture the "asymptotic" behavior of algorithms, we also develope experiments by considering a widely used graph from the real world, i.e., the Internet graph. Work partially supported by the ESPRIT Long Term Research Project...