Member

Description

reference

A proxy class that acts as a reference to a single bit. It contains
an assignment operator, a conversion to bool, an operator~, and
a member function flip. It exists only as a helper class for
bitset's operator[]. That is, it supports the expressions
x = b[i], b[i] = x, b[i] = b[j], x = ~b[i], and
b[i].flip(). (Where b is a bitset and x is a bool.)

bitset(unsigned long val)

Conversion from unsigned long. Constructs a bitset, initializing
the first min(N, sizeof(unsigned long) * CHAR_BIT) bits to the
corresponding bits in val and all other bits, if any, to zero.

template<class Char, class Traits, class Alloc>
explicit
bitset(const basic_string<Char,Traits,Alloc>& s,
size_t pos = 0,
size_t n =
basic_string<Char,Traits,Alloc>::npos)

Conversion from string. Constructs a bitset, initializing the
first M bits to the corresponding characters in s, where
M is defined as min(N, min(s.size()  pos, n)).
Note that the highest character position in s, not the
lowest, corresponds to the least significant bit.
That is, character position pos + M  1  i corresponds to bit i.
So, for example, bitset(string("1101")) is the same as
bitset(13ul). This function throws out_of_range if
pos > s.size(), and invalid_argument if any of the characters
used to initialize the bits are anything other than 0 or 1.

bitset& operator&=(const bitset&)

Bitwise and.

bitset& operator=(const bitset&)

Bitwise inclusive or.

bitset& operator^=(const bitset&)

Bitwise exclusive or.

bitset& operator<<=(size_t n)

Left shift, where bit 0 is considered the least significant bit.
Bit i takes on the previous value of bit i  n, or zero if no
such bit exists.

bitset& operator>>=(size_t n)

Right shift, where bit 0 is considered the least significant bit.
Bit i takes on the previous value of bit i + n, or zero if no
such bit exists.

bitset operator<<(size_t n) const

Returns a copy of *this shifted left by n bits.
Note that the expression b << n is equivalent to
constructing a temporary copy of b
and then using operator<<=.

bitset operator>>(size_t n) const

Returns a copy of *this shifted right by n bits.
Note that the expression b >> n is equivalent to
constructing a temporary copy of b
and then using operator>>=.

bitset& set()

Sets every bit.

bitset& flip()

Flips the value of every bit.

bitset operator~() const

Returns a copy of *this with all of its bits flipped.

bitset& reset()

Clears every bit.

bitset& set(size_t n, int val = 1)

Sets bit n if val is nonzero, and clears bit n if val is zero.
Throws out_of_range if n >= N.

bitset& reset(size_t n)

Clears bit n.
Throws out_of_range if n >= N.

bitset flip(size_t n)

Flips bit n.
Throws out_of_range if n >= N.

size_t size() const

Returns N.

size_t count() const

Returns the number of bits that are set.

bool any() const

Returns true if any bits are set.

bool none() const

Returns true if no bits are set.

bool test(size_t n) const

Returns true if bit n is set.
Throws out_of_range if n >= N.

reference operator[](size_t n)

Returns a reference to bit n. Note that reference is a
proxy class with an assignment operator and a conversion to bool,
which allows you to use operator[] for assignment. That is, you
can write both x = b[n] and b[n] = x.

bool operator[](size_t n) const

Returns true if bit n is set.

unsigned long to_ulong() const

Returns an unsigned long corresponding to the bits in *this.
Throws overflow_error if it is impossible to represent *this as
an unsigned long. (That is, if N is larger than the number of
bits in an unsigned long and if any of the highorder bits are set.

template<class Char, class Traits, class Alloc>
basic_string<Char,Traits,Alloc> to_string() const

Returns a string representation of *this: each character is
1 if the corresponding bit is set, and 0 if it is not.
In general, character position i corresponds to bit position
N  1  i. Note that this member function relies on two
language features, member templates and explicit function
template argument specification, that are not yet universally
available; this member function is disabled for compilers that do
not support those features. Note also that the syntax for calling
this member function is somewhat cumbersome. To convert a bitset b
to an ordinary string, you must write
b.template to_string<char, char_traits<char>, allocator<char> >()

bitset operator&(const bitset&, const bitset&)

Bitwise and of two bitsets. This is a global function,
not a member function. Note that the expression b1 & b2
is equivalent to creating a temporary copy of b1, using
operator&=, and returning the temporary copy.

bitset operator(const bitset&, const bitset&)

Bitwise or of two bitsets. This is a global function,
not a member function. Note that the expression b1  b2
is equivalent to creating a temporary copy of b1, using
operator=, and returning the temporary copy.

bitset operator^(const bitset&, const bitset&)

Bitwise exclusive or of two bitsets. This is a global function,
not a member function. Note that the expression b1 ^ b2
is equivalent to creating a temporary copy of b1, using
operator^=, and returning the temporary copy.

template <class Char, class Traits,
size_t N>
basic_istream<Char, Traits>&
operator>>(basic_istream<Char,Traits>& is,
bitset<N>& x)

Extract a bitset from an input stream. This function first
skips whitespace, then extracts up to N characters from the
input stream. It stops either when it has successfully
extracted N character, or when extraction fails, or when
it sees a character that is something other than 1 (in which
case it does not extract that character). It then assigns a
value to the bitset in the same way as if it were initializing
the bitset from a string. So, for example, if the input stream
contains the characters "1100abc", it will assign the value
12ul to the bitset, and the next character read from the input
stream will be a.

template <class Char, class Traits,
size_t N>
basic_ostream<Char,Traits>&
operator<<(basic_ostream<Char,Traits>& os,
const bitset<N>& x)

Output a bitset to an output stream. This function behaves as
if it converts the bitset to a string and then writes that string
to the output stream. That is, it is equivalent to
os << x.template to_string<Char,Traits,allocator<Char> >()
