pm::Bitset Class Reference

Container class for dense sets of integers. More...

Inheritance diagram for pm::Bitset:

Collaboration diagram for pm::Bitset:

Public Types
typedef int	element_type
	element types
typedef operations::cmp	element_comparator
	functor type for comparing elements
typedef GenericSet	generic_type
	generic type
typedef Generic< Bitset >::top_type	top_type
	top type

Public Member Functions
	Bitset ()
	An empty set, with minimal preallocated storage.
	Bitset (int n, bool full=false)
	An empty set with preallocated storage for elements 0..n-1. More...
	Bitset (const GenericSet< Bitset > &s)
	Copy of a disguised Bitset object.
template<typename TSet >
	Bitset (const GenericSet< TSet, int > &s)
	Copy of an abstract set of integers.
template<typename TSet , typename E2 , typename Comparator2 , typename = typename std::enable_if<std::is_convertible<E2, int>::value>::type>
	Bitset (const GenericSet< TSet, E2, Comparator2 > &s)
	Copy of an abstract set with element conversion.
	Bitset (gmp_randstate_t rnd, unsigned long bits)
	Fill with a prescribed number of random bits.
Bitset &	operator= (const GenericSet< Bitset > &s)
	Assign elements from a disguised Bitset object.
void	reserve (int n)
	Reserve storage for n elements.
void	clear ()
	Make the set empty.
template<typename TSet >
Bitset &	operator= (const GenericSet< TSet, int > &s)
	Assign elements from an abstract set of integers.
int	size () const noexcept
Bitset &	operator+= (int i)
Bitset &	operator-= (int i)
Bitset &	operator-= (const Bitset &s)
	difference
Bitset &	operator*= (int i)
	intersection

Detailed Description

Container class for dense sets of integers.

A special class optimized for representation of a constrained range of non-negative integer numbers. Its implementation is based on the GMP (mpz_t), see http://www.swox.com/gmp/ You should consider to use it instead of the more general Set<int> if all these criteria hold:

• the element range stays constant during the lifetime of the set
• the element range is small (magnitude of tens), or the fill grade (number of elements divided through the element upper bound) is expected to be rather high (>= 0.5)
• the number of random access operations (testing/addition/removal of single elements) prevails significantly over the number of sequential visits via iterators

Note that unlike std::bitset, the element range is not hard encoded in the Bitset object, but can be dynamically changed any time.

Constructor & Destructor Documentation

pm::Bitset::Bitset ( int  n, bool  full = false  )

inlineexplicit

An empty set with preallocated storage for elements 0..n-1.

It can dynamically grow beyond this limit if needed; to avoid performance penalties, however, you should specify here the highest element you really expect to occur.

Parameters

n
full	Set this to 1 if the set contains all elements from 0 to n-1, defaults to 0.

Member Function Documentation

Bitset& pm::Bitset::operator+= ( int  i )

inline

Insert an element. This is the quickest way to manipulate single elements.

Bitset& pm::Bitset::operator-= ( int  i )

inline

Remove an element if it existed. This is the quickest way to manipulate single elements.

int pm::Bitset::size ( ) const

inlinenoexcept

Count the elements. CAUTION: depending on the hardware, can take O(n) time!

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The documentation for this class was generated from the following file:

• lib/core/include/Bitset.h