/*

 * © Portions copyright (c) 2006-2007 Nokia Corporation.  All rights reserved.

 * Copyright (c) 1998

 * Silicon Graphics Computer Systems, Inc.

 *

 * Copyright (c) 1999 

 * Boris Fomitchev

 *

 * This material is provided "as is", with absolutely no warranty expressed

 * or implied. Any use is at your own risk.

 *

 * Permission to use or copy this software for any purpose is hereby granted 

 * without fee, provided the above notices are retained on all copies.

 * Permission to modify the code and to distribute modified code is granted,

 * provided the above notices are retained, and a notice that the code was

 * modified is included with the above copyright notice.

 *

 */

#ifndef _STLP_BITSET_H

#define _STLP_BITSET_H

// A bitset of size N has N % (sizeof(unsigned long) * CHAR_BIT) unused 

// bits.  (They are the high- order bits in the highest word.)  It is

// a class invariant of class bitset<> that those unused bits are

// always zero.

// Most of the actual code isn't contained in bitset<> itself, but in the 

// base class _Base_bitset.  The base class works with whole words, not with

// individual bits.  This allows us to specialize _Base_bitset for the

// important special case where the bitset is only a single word.

// The C++ standard does not define the precise semantics of operator[].

// In this implementation the const version of operator[] is equivalent

// to test(), except that it does no range checking.  The non-const version

// returns a reference to a bit, again without doing any range checking.

# ifndef _STLP_INTERNAL_ALGOBASE_H

#  include <stl/_algobase.h>

# endif

# ifndef _STLP_INTERNAL_ALLOC_H

#  include <stl/_alloc.h>

# endif

# ifndef _STLP_INTERNAL_ITERATOR_H

#  include <stl/_iterator.h>

# endif

# ifndef _STLP_INTERNAL_UNINITIALIZED_H

#  include <stl/_uninitialized.h>

# endif

# ifndef _STLP_RANGE_ERRORS_H

#  include <stl/_range_errors.h>

# endif

# ifndef _STLP_STRING

#  include <string>

# endif

# ifndef _STLP_ISTREAM

#  include <istream>

# endif

#define __BITS_PER_WORD (CHAR_BIT*sizeof(unsigned long))

#define __BITSET_WORDS(__n) ((__n + __BITS_PER_WORD - 1)/__BITS_PER_WORD)

_STLP_BEGIN_NAMESPACE

// structure to aid in counting bits

template<class _Dummy> 

class _Bs_G {

public:

  static const unsigned char _S_bit_count[256];

  // Mapping from 8 bit unsigned integers to the index of the first one

  // bit:

  static const unsigned char _S_first_one[256];

};

//

// Base class: general case.

//

template<size_t _Nw>

struct _Base_bitset {

  typedef unsigned long _WordT;

  _WordT _M_w[_Nw];                // 0 is the least significant word.

  _Base_bitset( void ) { _M_do_reset(); }

  _Base_bitset(unsigned long __val) {

    _M_do_reset();

    _M_w[0] = __val;

  }

  static size_t _STLP_CALL _S_whichword( size_t __pos ) {

    return __pos / __BITS_PER_WORD;

  }

  static size_t _STLP_CALL _S_whichbyte( size_t __pos ) {

    return (__pos % __BITS_PER_WORD) / CHAR_BIT;

  }

  static size_t _STLP_CALL _S_whichbit( size_t __pos ) {

    return __pos % __BITS_PER_WORD;

  }

  static _WordT _STLP_CALL _S_maskbit( size_t __pos ) {

    return __STATIC_CAST(_WordT,1) << _S_whichbit(__pos);

  }

  _WordT& _M_getword(size_t __pos)       { return _M_w[_S_whichword(__pos)]; }

  _WordT  _M_getword(size_t __pos) const { return _M_w[_S_whichword(__pos)]; }

  _WordT& _M_hiword()       { return _M_w[_Nw - 1]; }

  _WordT  _M_hiword() const { return _M_w[_Nw - 1]; }

  void _M_do_and(const _Base_bitset<_Nw>& __x) {

    for ( size_t __i = 0; __i < _Nw; __i++ ) {

      _M_w[__i] &= __x._M_w[__i];

    }

  }

  void _M_do_or(const _Base_bitset<_Nw>& __x) {

    for ( size_t __i = 0; __i < _Nw; __i++ ) {

      _M_w[__i] |= __x._M_w[__i];

    }

  }

  void _M_do_xor(const _Base_bitset<_Nw>& __x) {

    for ( size_t __i = 0; __i < _Nw; __i++ ) {

      _M_w[__i] ^= __x._M_w[__i];

    }

  }

  void _M_do_left_shift(size_t __shift);

  void _M_do_right_shift(size_t __shift);

  void _M_do_flip() {

    for ( size_t __i = 0; __i < _Nw; __i++ ) {

      _M_w[__i] = ~_M_w[__i];

    }

  }

  void _M_do_set() {

    for ( size_t __i = 0; __i < _Nw; __i++ ) {

      _M_w[__i] = ~__STATIC_CAST(_WordT,0);

    }

  }

  void _M_do_reset() { memset(_M_w, 0, _Nw * sizeof(_WordT)); }

  bool _M_is_equal(const _Base_bitset<_Nw>& __x) const {

    for (size_t __i = 0; __i < _Nw; ++__i) {

      if (_M_w[__i] != __x._M_w[__i])

        return false;

    }

    return true;

  }

  bool _M_is_any() const {

    for ( size_t __i = 0; __i < _Nw ; __i++ ) {

      if ( _M_w[__i] != __STATIC_CAST(_WordT,0) )

        return true;

    }

    return false;

  }

  size_t _M_do_count() const {

    size_t __result = 0;

    const unsigned char* __byte_ptr = (const unsigned char*)_M_w;

    const unsigned char* __end_ptr = (const unsigned char*)(_M_w+_Nw);

    while ( __byte_ptr < __end_ptr ) {

      __result += _Bs_G<bool>::_S_bit_count[*__byte_ptr];

      __byte_ptr++;

    }

    return __result;

  }

  unsigned long _M_do_to_ulong() const; 

  // find first "on" bit

  size_t _M_do_find_first(size_t __not_found) const;

  // find the next "on" bit that follows "prev"

  size_t _M_do_find_next(size_t __prev, size_t __not_found) const;

};

//

// Base class: specialization for a single word.

//

_STLP_TEMPLATE_NULL

struct _Base_bitset<1UL> {

  typedef unsigned long _WordT;

  typedef _Base_bitset<1UL> _Self;

  _WordT _M_w;

  _Base_bitset( void ) : _M_w(0) {}

  _Base_bitset(unsigned long __val) : _M_w(__val) {}

  static size_t _STLP_CALL _S_whichword( size_t __pos ) {

    return __pos / __BITS_PER_WORD ;

  }

  static size_t _STLP_CALL _S_whichbyte( size_t __pos ) {

    return (__pos % __BITS_PER_WORD) / CHAR_BIT;

  }

  static size_t _STLP_CALL _S_whichbit( size_t __pos ) {

    return __pos % __BITS_PER_WORD;

  }

  static _WordT _STLP_CALL _S_maskbit( size_t __pos ) {

    return (__STATIC_CAST(_WordT,1)) << _S_whichbit(__pos);

  }

  _WordT& _M_getword(size_t)       { return _M_w; }

  _WordT  _M_getword(size_t) const { return _M_w; }

  _WordT& _M_hiword()       { return _M_w; }

  _WordT  _M_hiword() const { return _M_w; }

  void _M_do_and(const _Self& __x) { _M_w &= __x._M_w; }

  void _M_do_or(const _Self& __x)  { _M_w |= __x._M_w; }

  void _M_do_xor(const _Self& __x) { _M_w ^= __x._M_w; }

  void _M_do_left_shift(size_t __shift)     { _M_w <<= __shift; }

  void _M_do_right_shift(size_t __shift)    { _M_w >>= __shift; }

  void _M_do_flip()                       { _M_w = ~_M_w; }

  void _M_do_set()                        { _M_w = ~__STATIC_CAST(_WordT,0); }

  void _M_do_reset()                      { _M_w = 0; }

  bool _M_is_equal(const _Self& __x) const {

    return _M_w == __x._M_w;

  }

  bool _M_is_any() const {

    return _M_w != 0;

  }

  size_t _M_do_count() const {

    size_t __result = 0;

    const unsigned char* __byte_ptr = (const unsigned char*)&_M_w;

    const unsigned char* __end_ptr = ((const unsigned char*)&_M_w)+sizeof(_M_w);

    while ( __byte_ptr < __end_ptr ) {

      __result += _Bs_G<bool>::_S_bit_count[*__byte_ptr];

      __byte_ptr++;

    }

    return __result;

  }

  unsigned long _M_do_to_ulong() const { return _M_w; }

  inline size_t _M_do_find_first(size_t __not_found) const;

  // find the next "on" bit that follows "prev"

  inline size_t _M_do_find_next(size_t __prev, size_t __not_found) const; 

};

// ------------------------------------------------------------

//

// Definitions of should-be-non-inline functions from the single-word version of

//  _Base_bitset.

//

inline size_t 

_Base_bitset<1UL>::_M_do_find_first(size_t __not_found) const

{

  //  typedef unsigned long _WordT;

  _WordT __thisword = _M_w;

  if ( __thisword != __STATIC_CAST(_WordT,0) ) {

    // find byte within word

    for ( size_t __j = 0; __j < sizeof(_WordT); __j++ ) {

      unsigned char __this_byte

        = __STATIC_CAST(unsigned char,(__thisword & (~(unsigned char)0)));

      if ( __this_byte )

        return __j*CHAR_BIT + _Bs_G<bool>::_S_first_one[__this_byte];

      __thisword >>= CHAR_BIT;

    }

  }

  // not found, so return a value that indicates failure.

  return __not_found;

}

inline size_t 

_Base_bitset<1UL>::_M_do_find_next(size_t __prev, 

                                   size_t __not_found ) const

{

  // make bound inclusive

  ++__prev;

  // check out of bounds

  if ( __prev >= __BITS_PER_WORD )

    return __not_found;

    // search first (and only) word

  _WordT __thisword = _M_w;

  // mask off bits below bound

  __thisword &= (~__STATIC_CAST(_WordT,0)) << _S_whichbit(__prev);

  if ( __thisword != __STATIC_CAST(_WordT,0) ) {

    // find byte within word

    // get first byte into place

    __thisword >>= _S_whichbyte(__prev) * CHAR_BIT;

    for ( size_t __j = _S_whichbyte(__prev); __j < sizeof(_WordT); __j++ ) {

      unsigned char __this_byte

        = __STATIC_CAST(unsigned char,(__thisword & (~(unsigned char)0)));

      if ( __this_byte )

        return __j*CHAR_BIT + _Bs_G<bool>::_S_first_one[__this_byte];

      __thisword >>= CHAR_BIT;

    }

  }

  // not found, so return a value that indicates failure.

  return __not_found;

} // end _M_do_find_next

// ------------------------------------------------------------

// Helper class to zero out the unused high-order bits in the highest word.

template <size_t _Extrabits> struct _Sanitize {

  static void _STLP_CALL _M_do_sanitize(unsigned long& __val)

    { __val &= ~((~__STATIC_CAST(unsigned long,0)) << _Extrabits); }

};

_STLP_TEMPLATE_NULL struct _Sanitize<0UL> {

  static void _STLP_CALL _M_do_sanitize(unsigned long) {}

};

// ------------------------------------------------------------

// Class bitset.

//   _Nb may be any nonzero number of type size_t.

template<size_t _Nb>

class bitset : public _Base_bitset<__BITSET_WORDS(_Nb) > 

{

public:

  enum { _Words = __BITSET_WORDS(_Nb) } ;

private:

  typedef _Base_bitset< _Words > _Base;

  void _M_do_sanitize() {

    _Sanitize<_Nb%__BITS_PER_WORD >::_M_do_sanitize(this->_M_hiword());

  }

public:

  typedef unsigned long _WordT;

  struct reference;

  friend struct reference;

  // bit reference:

  struct reference {

  typedef _Base_bitset<_Words > _Bitset_base;

  typedef bitset<_Nb> _Bitset;

    //    friend _Bitset;

    _WordT *_M_wp;

    size_t _M_bpos;

    // should be left undefined

    reference() {}

    reference( _Bitset& __b, size_t __pos ) {

      _M_wp = &__b._M_getword(__pos);

      _M_bpos = _Bitset_base::_S_whichbit(__pos);

    }

  public:

    ~reference() {}

    // for b[i] = __x;

    reference& operator=(bool __x) {

      if ( __x )

        *_M_wp |= _Bitset_base::_S_maskbit(_M_bpos);

      else

        *_M_wp &= ~_Bitset_base::_S_maskbit(_M_bpos);

      return *this;

    }

    // for b[i] = b[__j];

    reference& operator=(const reference& __j) {

      if ( (*(__j._M_wp) & _Bitset_base::_S_maskbit(__j._M_bpos)) )

        *_M_wp |= _Bitset_base::_S_maskbit(_M_bpos);

      else

        *_M_wp &= ~_Bitset_base::_S_maskbit(_M_bpos);

      return *this;

    }

    // flips the bit

    bool operator~() const { return (*(_M_wp) & _Bitset_base::_S_maskbit(_M_bpos)) == 0; }

    // for __x = b[i];

    operator bool() const { return (*(_M_wp) & _Bitset_base::_S_maskbit(_M_bpos)) != 0; }

    // for b[i].flip();

    reference& flip() {

      *_M_wp ^= _Bitset_base::_S_maskbit(_M_bpos);

      return *this;

    }

  };

  // 23.3.5.1 constructors:

  bitset() {}

  bitset(unsigned long __val) : _Base_bitset<_Words>(__val) { _M_do_sanitize(); }

# ifdef _STLP_MEMBER_TEMPLATES

  template<class _CharT, class _Traits, class _Alloc>

  explicit bitset(const basic_string<_CharT,_Traits,_Alloc>& __s,

                  size_t __pos = 0)

    : _Base_bitset<_Words >() 

  {

    if (__pos > __s.size()) 

      __stl_throw_out_of_range("bitset");

    _M_copy_from_string(__s, __pos,

                        basic_string<_CharT, _Traits, _Alloc>::npos);

  }

  template<class _CharT, class _Traits, class _Alloc>

  bitset(const basic_string<_CharT, _Traits, _Alloc>& __s,

          size_t __pos,

          size_t __n)

  : _Base_bitset<_Words >() 

  {

    if (__pos > __s.size()) 

      __stl_throw_out_of_range("bitset");

    _M_copy_from_string(__s, __pos, __n);

  }

#else /* _STLP_MEMBER_TEMPLATES */

  explicit bitset(const string& __s,

                  size_t __pos = 0,

                  size_t __n = (size_t)-1) 

    : _Base_bitset<_Words >() 

  {

    if (__pos > __s.size()) 

      __stl_throw_out_of_range("bitset");

    _M_copy_from_string(__s, __pos, __n);

  }

#endif /* _STLP_MEMBER_TEMPLATES */

  // 23.3.5.2 bitset operations:

  bitset<_Nb>& operator&=(const bitset<_Nb>& __rhs) {

    this->_M_do_and(__rhs);

    return *this;

  }

  bitset<_Nb>& operator|=(const bitset<_Nb>& __rhs) {

    this->_M_do_or(__rhs);

    return *this;

  }

  bitset<_Nb>& operator^=(const bitset<_Nb>& __rhs) {

    this->_M_do_xor(__rhs);

    return *this;

  }

  bitset<_Nb>& operator<<=(size_t __pos) {

#ifdef __SYMBIAN32__

	if(__pos < _Nb)

	{

    	this->_M_do_left_shift(__pos);

    	this->_M_do_sanitize();

	}

	else

		this->_M_do_reset();

#else

	this->_M_do_left_shift(__pos);

	this->_M_do_sanitize();

#endif

    return *this;

  }

  bitset<_Nb>& operator>>=(size_t __pos) {

#ifdef __SYMBIAN32__

	if(__pos < _Nb)

	{

    	this->_M_do_right_shift(__pos);

    	this->_M_do_sanitize();

	}

	else

		this->_M_do_reset();

#else

	this->_M_do_right_shift(__pos);

    this->_M_do_sanitize();

#endif

    return *this;

  }

  //

  // Extension:

  // Versions of single-bit set, reset, flip, test with no range checking.

  //

  bitset<_Nb>& _Unchecked_set(size_t __pos) {

    this->_M_getword(__pos) |= _Base_bitset<_Words > ::_S_maskbit(__pos);

    return *this;

  }

  bitset<_Nb>& _Unchecked_set(size_t __pos, int __val) {

    if (__val)

      this->_M_getword(__pos) |= this->_S_maskbit(__pos);

    else

      this->_M_getword(__pos) &= ~ this->_S_maskbit(__pos);

    return *this;

  }

  bitset<_Nb>& _Unchecked_reset(size_t __pos) {

    this->_M_getword(__pos) &= ~ this->_S_maskbit(__pos);

    return *this;

  }

  bitset<_Nb>& _Unchecked_flip(size_t __pos) {

    this->_M_getword(__pos) ^= this->_S_maskbit(__pos);

    return *this;

  }

  bool _Unchecked_test(size_t __pos) const {