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Contraction Hierarchies: Faster and Simpler Hierarchical Routing in Road Networks
TLDR
CHs can be combined with many other route planning techniques, leading to improved performance for many-to-many routing, transit-node routing, goal-directed routing or mobile and dynamic scenarios, and a hierarchical query algorithm using bidirectional shortest-path search is obtained.
Polynomial time algorithms for multicast network code construction
TLDR
Deterministic polynomial time algorithms and even faster randomized algorithms for designing linear codes for directed acyclic graphs with edges of unit capacity are given and extended to integer capacities and to codes that are tolerant to edge failures.
Exact Routing in Large Road Networks Using Contraction Hierarchies
TLDR
A mobile implementation of contraction hierarchies for fast routing in road networks that also handles changes in the road network, like traffic jams, and that allows instantaneous routing without noticeable delay for the user is presented.
Linear work suffix array construction
TLDR
A generalized algorithm, DC, that allows a space-efficient implementation and, moreover, supports the choice of a space--time tradeoff and is asymptotically faster than all previous suffix tree or array construction algorithms.
Route Planning in Transportation Networks
TLDR
It is shown that one can compute driving directions in milliseconds or less even at continental scale, and a variety of techniques provide different trade-offs between preprocessing effort, space requirements, and query time.
Simple Linear Work Suffix Array Construction
TLDR
The skew algorithm for suffix array construction over integer alphabets that can be implemented to run in linear time using integer sorting as its only nontrivial subroutine is introduced.
Δ-stepping: a parallelizable shortest path algorithm
TLDR
A rather simple algorithm for the single source shortest path problem, which the authors call Delta-stepping, can be implemented very efficiently in sequential and parallel setting for a large class of graphs and achieves significant speedup on real machines.
In Transit to Constant Time Shortest-Path Queries in Road Networks
TLDR
An algorithmic approach---transit node routing---that allows us to reduce quickest-path queries in road networks to a small number of table lookups is developed.
STXXL: standard template library for XXL data sets
TLDR
The software library STXXL is presented, an implementation of the C++ standard template library (STL) for processing huge data sets that can fit only on hard disks and it is the first I/O‐efficient algorithm library that supports the pipelining technique that can save more than half of the I/Os.
Better Approximation of Betweenness Centrality
TLDR
A framework for unbiased approximation of betweenness is proposed that generalizes a previous approach by Brandes and yields significantly better approximation than before for many real world inputs and good approximations for the betweenness of unimportant nodes.
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