
Grammar Compressed Sequences with Rank/Select Support
Sequence representations supporting not only direct access to their symb...
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Fast Dynamic Arrays
We present a highly optimized implementation of tiered vectors, a data s...
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Rank/Select Queries over Mutable Bitmaps
The problem of answering rank/select queries over a bitmap is of utmost ...
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On dynamic succinct graph representations
We address the problem of representing dynamic graphs using k^2trees. T...
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Compact Fenwick trees for dynamic ranking and selection
The Fenwick tree is a classical implicit data structure that stores an a...
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Sorting and Ranking of SelfDelimiting Numbers with Applications to Tree Isomorphism
Assume that an Nbit sequence S of k selfdelimiting numbers is given as...
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Compressed Data Structures for Binary Relations in Practice
Binary relations are commonly used in Computer Science for modeling data...
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Proving tree algorithms for succinct data structures
Succinct data structures give spaceefficient representations of large amounts of data without sacrificing performance. They rely one cleverly designed data representations and algorithms. We present here the formalization in Coq/SSReflect of two different treebased succinct representations and their accompanying algorithms. One is the LevelOrder Unary Degree Sequence, which encodes the structure of a tree in breadthfirst order as a sequence of bits, where access operations can be defined in terms of Rank and Select, which work in constant time for static bit sequences. The other represents dynamic bit sequences as binary balanced trees, where Rank and Select present a low logarithmic overhead compared to their static versions, and with efficient insertion and deletion. The two can be stacked to provide a dynamic representation of dictionaries for instance. While both representations are wellknown, we believe this to be their first formalization and a needed step towards provablysafe implementations of big data.
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