23 General utilities library [utilities]

23.9 Bitsets [bitset]

23.9.2 Class template bitset [template.bitset]

23.9.2.2 bitset members [bitset.members]

bitset<N>& operator&=(const bitset<N>& rhs) noexcept;

Effects: Clears each bit in *this for which the corresponding bit in rhs is clear, and leaves all other bits unchanged.

Returns: *this.

bitset<N>& operator|=(const bitset<N>& rhs) noexcept;

Effects: Sets each bit in *this for which the corresponding bit in rhs is set, and leaves all other bits unchanged.

Returns: *this.

bitset<N>& operator^=(const bitset<N>& rhs) noexcept;

Effects: Toggles each bit in *this for which the corresponding bit in rhs is set, and leaves all other bits unchanged.

Returns: *this.

bitset<N>& operator<<=(size_t pos) noexcept;

Effects: Replaces each bit at position I in *this with a value determined as follows:

  • If I < pos, the new value is zero;

  • If I >= pos, the new value is the previous value of the bit at position I - pos.

Returns: *this.

bitset<N>& operator>>=(size_t pos) noexcept;

Effects: Replaces each bit at position I in *this with a value determined as follows:

  • If pos >= N - I, the new value is zero;

  • If pos < N - I, the new value is the previous value of the bit at position I + pos.

Returns: *this.

bitset<N>& set() noexcept;

Effects: Sets all bits in *this.

Returns: *this.

bitset<N>& set(size_t pos, bool val = true);

Throws: out_­of_­range if pos does not correspond to a valid bit position.

Effects: Stores a new value in the bit at position pos in *this. If val is true, the stored value is one, otherwise it is zero.

Returns: *this.

bitset<N>& reset() noexcept;

Effects: Resets all bits in *this.

Returns: *this.

bitset<N>& reset(size_t pos);

Throws: out_­of_­range if pos does not correspond to a valid bit position.

Effects: Resets the bit at position pos in *this.

Returns: *this.

bitset<N> operator~() const noexcept;

Effects: Constructs an object x of class bitset<N> and initializes it with *this.

Returns: x.flip().

bitset<N>& flip() noexcept;

Effects: Toggles all bits in *this.

Returns: *this.

bitset<N>& flip(size_t pos);

Throws: out_­of_­range if pos does not correspond to a valid bit position.

Effects: Toggles the bit at position pos in *this.

Returns: *this.

unsigned long to_ulong() const;

Throws: overflow_­error if the integral value x corresponding to the bits in *this cannot be represented as type unsigned long.

Returns: x.

unsigned long long to_ullong() const;

Throws: overflow_­error if the integral value x corresponding to the bits in *this cannot be represented as type unsigned long long.

Returns: x.

template <class charT = char, class traits = char_traits<charT>, class Allocator = allocator<charT>> basic_string<charT, traits, Allocator> to_string(charT zero = charT('0'), charT one = charT('1')) const;

Effects: Constructs a string object of the appropriate type and initializes it to a string of length N characters. Each character is determined by the value of its corresponding bit position in *this. Character position N - 1 corresponds to bit position zero. Subsequent decreasing character positions correspond to increasing bit positions. Bit value zero becomes the character zero, bit value one becomes the character one.

Returns: The created object.

size_t count() const noexcept;

Returns: A count of the number of bits set in *this.

constexpr size_t size() const noexcept;

Returns: N.

bool operator==(const bitset<N>& rhs) const noexcept;

Returns: true if the value of each bit in *this equals the value of the corresponding bit in rhs.

bool operator!=(const bitset<N>& rhs) const noexcept;

Returns: true if !(*this == rhs).

bool test(size_t pos) const;

Throws: out_­of_­range if pos does not correspond to a valid bit position.

Returns: true if the bit at position pos in *this has the value one.

bool all() const noexcept;

Returns: count() == size().

bool any() const noexcept;

Returns: count() != 0.

bool none() const noexcept;

Returns: count() == 0.

bitset<N> operator<<(size_t pos) const noexcept;

Returns: bitset<N>(*this) <<= pos.

bitset<N> operator>>(size_t pos) const noexcept;

Returns: bitset<N>(*this) >>= pos.

constexpr bool operator[](size_t pos) const;

Requires: pos shall be valid.

Returns: true if the bit at position pos in *this has the value one, otherwise false.

Throws: Nothing.

bitset<N>::reference operator[](size_t pos);

Requires: pos shall be valid.

Returns: An object of type bitset<N>​::​reference such that (*this)[pos] == this->test(pos), and such that (*this)[pos] = val is equivalent to this->set(pos, val).

Throws: Nothing.

Remarks: For the purpose of determining the presence of a data race, any access or update through the resulting reference potentially accesses or modifies, respectively, the entire underlying bitset.