BITSCAN: a C++ library for bit strings

A comprehensive view of BITSCAN

BITSCAN is a C++ library dedicated to efficient processing of bit strings. In programming, a bit string is a data structure that stores collections of bits (ones and zeros). It gets interesting when these bits have semantics, i.e.  refer to a Boolean property of a group, so that each element is identified by a bit in the chain. In previous posts I have repeatedly stated that BITSCAN “is a useful library to manage bit strings”, and that was that. Readers of our blog have questioned the usefulness of bit strings in practice so I will start this post explaining some common situations in which bit strings may be an alternative to more common data structures.

Bit strings can now be processed more powerfully with BITSCAN hosted in biicode

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Bit-encoded Graphs

UPDATED: 11/09/2014

Today, by the hand of Pablo San Segundo, we present graph and ugraph, two simple, easy-to-use, C++ wrappers for unweighted graphs encoded as bit strings.

Preliminaries

One of the most interesting and versatile applications of bit strings is to encode simple unweighted graphs dynamic in the number of edges (i.e. there is an efficient way to add/remove edges but not so for the vertices). Graphs encoded as bit strings have recently attracted the attention of researchers in relation to  well known NP-hard problems such as vertex coloring or clique. The main reason is that efficient algorithms that exploit bit-parallelism at CPU level have been found for such problems.

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