windows-nt/Source/XPSP1/NT/multimedia/dshow/h/intset.h

// Copyright (c) 1996 - 1999  Microsoft Corporation.  All Rights Reserved.
#ifndef __IntSet_h__
#define __IntSet_h__

#include <stdlib.h>
#include <memory.h>

// To test this class, copy this file into a .cpp,
// load into Dev Studio, define self_test and run.
#ifdef self_test
    #include <iostream.h>
    #include <assert.h>
    #define ASSERT assert
#endif

// Class denoting a set of integers within the range [min..max]
// A number may be added to the set by +=,
// removed from the set by -=,
// and tested by [number].

class IntSet
{
protected:
    const int m_min, m_max;
    unsigned * m_pBits;
    enum { bit_width = 8 * sizeof(unsigned), low_mask = bit_width - 1, high_shift = 5 };

public:
    ~IntSet();
    IntSet( int min, int max );

    int Max() const { return m_max; }
    int Min() const { return m_min; }

    void Clear()
    {
        memset( m_pBits, 0, ((m_max - m_min) / bit_width + 1) * sizeof(unsigned) );
    }

    void operator += ( int elmt )
    {
        ASSERT( elmt >= m_min && elmt <= m_max );
        elmt -= m_min;
        m_pBits[elmt >> high_shift] |= 1 << (elmt & low_mask);
    }

    void operator -= ( int elmt )
    {
        ASSERT( elmt >= m_min && elmt <= m_max );
        elmt -= m_min;
        m_pBits[elmt >> high_shift] &= ~(1 << (elmt & low_mask));
    }

    int operator[] ( int elmt ) const
    {
        if (elmt < m_min) return 0;
        if (elmt > m_max) return 0;
        elmt -= m_min;
        return (m_pBits[elmt >> high_shift] >> (elmt & low_mask)) & 1;
    }

#ifdef self_test
    void COut() const
    {
        for (int i = m_min; i <= m_max; i++) cout << ( (*this)[i] ? 'Y' : 'n' );
        cout << endl;
    }
#endif
};

inline IntSet::~IntSet()
{
    delete [] m_pBits;
}

inline IntSet::IntSet( int min, int max )
: m_min(min), m_max(max)
{
    m_pBits = new unsigned [(max-min)/bit_width + 1];
    Clear();
}


// Variation that can only hold objects [0..31].
// An initial value can be specified on creation.
// Appart from its construction, this object should
// look like an IntSet.

class IntSmallSet
{
protected:
    enum { m_min = 0, m_max = 63 };
    unsigned __int64 m_Bits;

public:
    static const __int64 One;

    IntSmallSet( unsigned __int64 init = 0 )
    : m_Bits(init)
    {}

    int Max() const { return m_max; }
    int Min() const { return m_min; }

    void Clear()
    {
        m_Bits = 0;
    }

    void operator += ( int elmt )
    {
        ASSERT( elmt >= m_min && elmt <= m_max );
        elmt -= m_min;
        m_Bits |= One << elmt;
    }

    void operator -= ( int elmt )
    {
        ASSERT( elmt >= m_min && elmt <= m_max );
        elmt -= m_min;
        m_Bits &= ~(One << elmt);
    }

    int operator[] ( int elmt ) const
    {
        if (elmt < m_min) return 0;
        if (elmt > m_max) return 0;
        elmt -= m_min;

        // Eliminate compiler warning: The conditional expression is an
        // _int64, convert it to an int
        return ((m_Bits >> elmt) & 1)? 1 : 0;
    }

    IntSmallSet operator | ( const IntSmallSet & s ) const
    { return IntSmallSet( m_Bits | s.m_Bits ); }

    IntSmallSet operator & ( const IntSmallSet & s ) const
    { return IntSmallSet( m_Bits & s.m_Bits ); }

    IntSmallSet operator ~ () const
    { return IntSmallSet( ~m_Bits ); }


    int operator == ( const IntSmallSet & s ) const
    { return m_Bits == s.m_Bits; }

    int operator == ( unsigned i ) const
    { return m_Bits == i; }

#ifdef self_test
    void COut() const
    {
        for (int i = m_min; i <= m_max; i++) cout << ( (*this)[i] ? 'Y' : 'n' );
        cout << endl;
    }
#endif
};


#ifdef self_test
void main()
{
    // IntSet Set1(-30,+102);
    IntSmallSet Set1;

    int i;

    for ( i = Set1.Min(); i <= Set1.Max(); i++ )
    {
        Set1 += i;
        Set1.COut();
    }

    for ( i = Set1.Max(); i >= Set1.Min(); i-- )
    {
        Set1 -= i;
        Set1.COut();
    }
}
#endif

#endif