spot/lbtt/src/Bitset.h

626 lines
20 KiB
C++

/*
* Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005
* Heikki Tauriainen <Heikki.Tauriainen@tkk.fi>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#ifndef BITSET_H
#define BITSET_H
#include <config.h>
#include <string>
#include <iostream>
#include "Exception.h"
using namespace std;
/******************************************************************************
*
* A class for sets of bits.
*
*****************************************************************************/
class Bitset
{
public:
explicit Bitset /* Creates an empty bit */
(const unsigned long int capacity = 0); /* set. */
explicit Bitset /* Creates a bit set */
(const BitArray& bitarray, /* from a bit array. */
const unsigned long int capacity);
Bitset(const Bitset& bitset); /* Copy constructor. */
~Bitset(); /* Destructor. */
operator const BitArray&() const; /* A Bitset can always be
* cast into a constant
* BitArray.
*/
Bitset& operator=(const Bitset& bitset); /* Assignment operator. */
bool operator[](const unsigned long int index) /* Tell the value of a */
const; /* bit in a given index. */
bool test(const unsigned long int index) const;
bool operator==(const Bitset& bitset) const; /* Test whether two */
bool equal(const Bitset& bitset) const; /* Bitsets are equal. */
bool operator<=(const Bitset& bitset) const; /* Test whether `this' */
bool subset(const Bitset& bitset) const; /* Bitset is a subset
* of another Bitset.
*/
unsigned long int capacity() const; /* Tells the capacity of
* the bit set.
*/
unsigned long int count() const; /* Compute the number of
* 1-bits in the Bitset.
*/
unsigned long int hammingDistance /* Compute the Hamming */
(const Bitset& bitset) const; /* distance between two
* Bitsets.
*/
void set(); /* Set all bits in the bit
* set.
*/
void setBit(const unsigned long int index); /* Set a single bit in the
* bit set.
*/
void clear(); /* Clear all bits in the
* bit set.
*/
void clearBit(const unsigned long int index); /* Clear a single bit in
* the bit set.
*/
void flip(); /* Flip all bits in the
* bit set.
*/
void flipBit(const unsigned long int index); /* Flip a single bit in the
* bit set.
*/
unsigned long int find() const; /* Return the index of the
* first 1-bit in the bit
* set.
*/
void print(ostream& stream = cout) const; /* Print the bit set. */
string toString() const; /* Convert the Bitset into
* a string if 0's and 1's.
*/
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
class BitIndexException; /* An exception class for
* reporting indexing
* errors.
*/
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
private:
unsigned long int number_of_bits; /* Capacity of the bit
* set.
*/
BitArray bits; /* Storage for the bits. */
};
/******************************************************************************
*
* An exception class for reporting bitset indexing errors.
*
*****************************************************************************/
class Bitset::BitIndexException : public Exception
{
public:
BitIndexException(); /* Constructor. */
/* default copy constructor */
~BitIndexException() throw(); /* Destructor. */
BitIndexException& /* Assignment operator. */
operator=(const BitIndexException& e);
/* `what' inherited from class Exception */
};
/******************************************************************************
*
* Inline function definitions for class Bitset.
*
*****************************************************************************/
/* ========================================================================= */
inline Bitset::Bitset(const unsigned long int capacity) :
number_of_bits(capacity), bits(capacity)
/* ----------------------------------------------------------------------------
*
* Description: Constructor for class Bitset.
*
* Argument: capacity -- Number of bits to allocate.
*
* Returns: Nothing.
*
* ------------------------------------------------------------------------- */
{
}
/* ========================================================================= */
inline Bitset::Bitset
(const BitArray& bitarray, const unsigned long int capacity) :
number_of_bits(capacity), bits(capacity)
/* ----------------------------------------------------------------------------
*
* Description: Constructor for class Bitset. Creates a Bitset from the
* first `capacity' bits of a BitArray.
*
* Arguments: bitarray -- A reference to a constant BitArray.
* capacity -- Capacity of the new bit set.
*
* Returns: Nothing.
*
* ------------------------------------------------------------------------- */
{
memcpy(static_cast<void*>(bits.bits),
static_cast<const void*>(bitarray.bits),
(capacity + 7) >> 3);
}
/* ========================================================================= */
inline Bitset::Bitset(const Bitset& bitset) :
number_of_bits(bitset.number_of_bits), bits(bitset.number_of_bits)
/* ----------------------------------------------------------------------------
*
* Description: Copy constructor for class Bitset.
*
* Argument: bitset -- Bitset to be copied.
*
* Returns: Nothing.
*
* ------------------------------------------------------------------------- */
{
memcpy(static_cast<void*>(bits.bits),
static_cast<const void*>(bitset.bits.bits),
(number_of_bits + 7) >> 3);
}
/* ========================================================================= */
inline Bitset::~Bitset()
/* ----------------------------------------------------------------------------
*
* Description: Destructor for class Bitset.
*
* Arguments: None.
*
* Returns: Nothing.
*
* ------------------------------------------------------------------------- */
{
}
/* ========================================================================= */
inline Bitset::operator const BitArray&() const
/* ----------------------------------------------------------------------------
*
* Description: Converts a Bitset into a BitArray.
*
* Arguments: None.
*
* Returns: The bits associated with the Bitset object as a reference to
* a constant BitArray.
*
* ------------------------------------------------------------------------- */
{
return bits;
}
/* ========================================================================= */
inline Bitset& Bitset::operator=(const Bitset& bitset)
/* ----------------------------------------------------------------------------
*
* Description: Assignment operator for class Bitset.
*
* Arguments: bitset -- A reference to a Bitset to be assigned to `this'
* Bitset.
*
* Returns: Nothing.
*
* ------------------------------------------------------------------------- */
{
if (&bitset != this)
{
if ((number_of_bits >> 3) != (bitset.number_of_bits >> 3))
bits.copy(bitset.bits, number_of_bits);
else
memcpy(static_cast<void*>(bits.bits),
static_cast<const void*>(bitset.bits.bits),
(bitset.number_of_bits + 7) >> 3);
number_of_bits = bitset.number_of_bits;
}
return *this;
}
/* ========================================================================= */
inline bool Bitset::operator[](const unsigned long int index) const
/* ----------------------------------------------------------------------------
*
* Description: Tells the state of a bit in a bit set.
*
* Argument: index -- Index of the bit to test.
*
* Returns: Truth value according to the state of the bit.
*
* ------------------------------------------------------------------------- */
{
if (index >= number_of_bits)
throw BitIndexException();
return bits[index];
}
/* ========================================================================= */
inline bool Bitset::test(const unsigned long int index) const
/* ----------------------------------------------------------------------------
*
* Description: Tells the state of a bit in a bit set.
*
* Argument: index -- Index of bit to test.
*
* Returns: Truth value according to the state of the bit.
*
* ------------------------------------------------------------------------- */
{
return operator[](index);
}
/* ========================================================================= */
inline bool Bitset::operator==(const Bitset& bitset) const
/* ----------------------------------------------------------------------------
*
* Description: Compares two bitsets for equality.
*
* Argument: bitset -- Target of the comparison.
*
* Returns: `true' if the bit sets have the same capacity and contents.
*
* ------------------------------------------------------------------------- */
{
return (number_of_bits == bitset.number_of_bits
&& bits.equal(bitset.bits, number_of_bits));
}
/* ========================================================================= */
inline bool Bitset::equal(const Bitset& bitset) const
/* ----------------------------------------------------------------------------
*
* Description: Compares two bitsets for equality.
*
* Argument: bitset -- Target of the comparison.
*
* Returns: `true' if the bit sets have the same capacity and contents.
*
* ------------------------------------------------------------------------- */
{
return operator==(bitset);
}
/* ========================================================================= */
inline bool Bitset::operator<=(const Bitset& bitset) const
/* ----------------------------------------------------------------------------
*
* Description: Tests whether `this' bitset is a subset of another Bitset.
*
* Argument: bitset -- Target of the comparison.
*
* Returns: `true' if the capacity of `this' bitset is at most equal to
* the capacity of the target bitset and all bits set in `this'
* Bitset are also set in the other set.
*
* ------------------------------------------------------------------------- */
{
return (number_of_bits <= bitset.number_of_bits
&& bits.subset(bitset.bits, number_of_bits));
}
/* ========================================================================= */
inline bool Bitset::subset(const Bitset& bitset) const
/* ----------------------------------------------------------------------------
*
* Description: Tests whether `this' bitset is a subset of another Bitset.
*
* Argument: bitset -- Target of the comparison.
*
* Returns: `true' if the capacity of `this' bitset is at most equal to
* the capacity of the target bitset and all bits set in `this'
* Bitset are also set in the other set.
*
* ------------------------------------------------------------------------- */
{
return operator<=(bitset);
}
/* ========================================================================= */
inline unsigned long int Bitset::capacity() const
/* ----------------------------------------------------------------------------
*
* Description: Tells the capacity of the bit set.
*
* Arguments: None.
*
* Returns: Capacity of the bit set.
*
* ------------------------------------------------------------------------- */
{
return number_of_bits;
}
/* ========================================================================= */
inline unsigned long int Bitset::count() const
/* ----------------------------------------------------------------------------
*
* Description: Computes the number of 1-bits in the Bitset.
*
* Arguments: None.
*
* Returns: Number of 1-bits in the Bitset.
*
* ------------------------------------------------------------------------- */
{
return bits.count(number_of_bits);
}
/* ========================================================================= */
inline unsigned long int Bitset::hammingDistance(const Bitset& bitset) const
/* ----------------------------------------------------------------------------
*
* Description: Computes the Hamming distance between two Bitsets (or between
* maximal prefixes of both Bitsets if the sets are of
* different capacity).
*
* Argument: bitset -- A reference to a constant Bitset.
*
* Returns: The Hamming distance between the bitsets (or their maximal
* prefixes of equal length).
*
* ------------------------------------------------------------------------- */
{
return bits.hammingDistance(bitset.bits,
number_of_bits <= bitset.number_of_bits
? number_of_bits
: bitset.number_of_bits);
}
/* ========================================================================= */
inline void Bitset::set()
/* ----------------------------------------------------------------------------
*
* Description: Fills the bit set with 1-bits.
*
* Arguments: None.
*
* Returns: Nothing.
*
* ------------------------------------------------------------------------- */
{
bits.set(number_of_bits);
}
/* ========================================================================= */
inline void Bitset::setBit(const unsigned long int index)
/* ----------------------------------------------------------------------------
*
* Description: Sets a single bit in the bit set.
*
* Argument: index -- Index of the bit to be set.
*
* Returns: Nothing.
*
* ------------------------------------------------------------------------- */
{
if (index >= number_of_bits)
throw BitIndexException();
bits.setBit(index);
}
/* ========================================================================= */
inline void Bitset::clear()
/* ----------------------------------------------------------------------------
*
* Description: Fills the bit set with 0-bits.
*
* Arguments: None.
*
* Returns: Nothing.
*
* ------------------------------------------------------------------------- */
{
bits.clear(number_of_bits);
}
/* ========================================================================= */
inline void Bitset::clearBit(const unsigned long int index)
/* ----------------------------------------------------------------------------
*
* Description: Clears a single bit in the bit set.
*
* Argument: index -- Index of the bit to be cleared.
*
* Returns: Nothing.
*
* ------------------------------------------------------------------------- */
{
if (index >= number_of_bits)
throw BitIndexException();
bits.clearBit(index);
}
/* ========================================================================= */
inline void Bitset::flip()
/* ----------------------------------------------------------------------------
*
* Description: Flips all bits in the bit set.
*
* Arguments: None.
*
* Returns: Nothing.
*
* ------------------------------------------------------------------------- */
{
bits.flip(number_of_bits);
}
/* ========================================================================= */
inline void Bitset::flipBit(const unsigned long int index)
/* ----------------------------------------------------------------------------
*
* Description: Switches the state of a single bit in the bit set.
*
* Arguments: index -- Index of the bit.
*
* Returns: Nothing.
*
* ------------------------------------------------------------------------- */
{
if (index >= number_of_bits)
throw BitIndexException();
bits.flipBit(index);
}
/* ========================================================================= */
inline unsigned long int Bitset::find() const
/* ----------------------------------------------------------------------------
*
* Description: Finds the index of the first 1-bit in the bit set.
*
* Arguments: None.
*
* Returns: Index of the first 1-bit in the bit set (or
* `this->number_of_bits' if the bit set is empty).
*
* ------------------------------------------------------------------------- */
{
return bits.find(number_of_bits);
}
/* ========================================================================= */
inline void Bitset::print(ostream& stream) const
/* ----------------------------------------------------------------------------
*
* Description: Writes the Bitset into a stream.
*
* Argument: stream -- A reference to an output stream.
*
* Returns: Nothing.
*
* ------------------------------------------------------------------------- */
{
bits.print(number_of_bits, stream);
}
/* ========================================================================= */
inline string Bitset::toString() const
/* ----------------------------------------------------------------------------
*
* Description: Converts the Bitset into a string.
*
* Arguments: None.
*
* Returns: A string representation of the Bitset.
*
* ------------------------------------------------------------------------- */
{
return bits.toString(number_of_bits);
}
/******************************************************************************
*
* Inline function definitions for class Bitset::BitIndexException.
*
*****************************************************************************/
/* ========================================================================= */
inline Bitset::BitIndexException::BitIndexException() :
Exception("Index out of range.")
/* ----------------------------------------------------------------------------
*
* Description: Constructor for class Bitset::BitIndexException. Creates a
* new exception object.
*
* Arguments: None.
*
* Returns: Nothing.
*
* ------------------------------------------------------------------------- */
{
}
/* ========================================================================= */
inline Bitset::BitIndexException::~BitIndexException() throw()
/* ----------------------------------------------------------------------------
*
* Description: Destructor for class Bitset::BitIndexException.
*
* Arguments: None.
*
* Returns: Nothing.
*
* ------------------------------------------------------------------------- */
{
}
/* ========================================================================= */
inline Bitset::BitIndexException& Bitset::BitIndexException::operator=
(const Bitset::BitIndexException& e)
/* ----------------------------------------------------------------------------
*
* Description: Assignment operator for class Bitset::BitIndexException.
*
* Arguments: e -- A reference to another Bitset::BitIndexException.
*
* Returns: A reference to the assigned exception object.
*
* ------------------------------------------------------------------------- */
{
Exception::operator=(e);
return *this;
}
#endif /* !BITSET_H */