Peter Sanders

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The famous max-flow min-cut theorem states that a source node s can send information through a network (V, E) to a sink node t at a rate determined by the min-cut separating s and t. Recently, it has been shown that this rate can also be achieved for multicasting to several sinks provided that the intermediate nodes are allowed to re-encode the information(More)
We present a route planning technique solely based on the concept of node contraction. The nodes are first ordered by ‘importance’. A hierarchy is then generated by iteratively contracting the least important node. Contracting a node v means replacing shortest paths going through v by shortcuts. We obtain a hierarchical query algorithm using bidirectional(More)
A suffix array represents the suffixes of a string in sorted order. Being a simpler and more compact alternative to suffix trees, it is an important tool for full text indexing and other string processing tasks. We introduce the skew algorithm for suffix array construction over integer alphabets that can be implemented to run in linear time using integer(More)
We present the software library STXXL that is an implementation of the C++ standard template library STL for processing huge data sets that can fit only on hard disks. It supports parallel disks, overlapping between disk I/O and computation and it is the first I/O-efficient algorithm library that supports the pipelining technique that can save more than(More)
Highway hierarchies exploit hierarchical properties inherent in real-world road networks to allow fast and exact point-to-point shortest-path queries. A fast preprocessing routine iteratively performs two steps: First, it removes edges that only appear on shortest paths <i>close</i> to source or target; second, it identifies low-degree nodes and bypasses(More)
Abstract. High performance applications involving large data sets require the efficient and flexible use of multiple disks. In an external memory machine with D parallel, independent disks, only one block can be accessed on each disk in one I/ O step. This restriction leads to a load balancing problem that is perhaps the main inhibitor for the efficient(More)
C hierarchies are a simple approach for fast routing in road networks. Our algorithm calculates exact shortest paths and handles road networks of whole continents. During a preprocessing step, we exploit the inherent hierarchical structure of road networks by adding shortcut edges. A subsequent modified bidirectional Dijkstra algorithm can then find a(More)
We generalize Cuckoo Hashing to d-ary Cuckoo Hashing and show how this yields a simple hash table data structure that stores n elements in (1 + ε)n memory cells, for any constant ε > 0. Assuming uniform hashing, accessing or deleting table entries takes at most d=O (ln (1/ε)) probes and the expected amortized insertion time is constant. This is the first(More)