Standard library header <bitset>

C++

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Headers

Freestanding and hosted implementations

Named requirements

Language support library

Concepts library (C++20)

Diagnostics library

Utilities library

Strings library

Containers library

Algorithms library

Iterators library

Numerics library

Input/output library

Localizations library

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Filesystem library (C++17)

Technical Specifications

Standard Library header files

Language Support
<cstddef> <limits> <climits> <contract>	<cfloat> <cstdint> <new> <version>	<typeinfo> <exception> <initializer_list>	<csignal> <csetjmp> <cstdarg>
Concepts
<concepts>
Diagnostics
<stdexcept>	<cassert>	<cerrno>	<system_error>
General utilities
<utility> <memory> <memory_resource> <scoped_allocator> <compare>	<bitset> <tuple> <optional> <any> <variant>	<type_traits> <ratio> <chrono> <typeindex> <functional>	<ctime> <cstdlib>
Strings
<string> <string_view>	<cctype> <cwctype>	<cwchar> <cuchar>	<cstring> <charconv>
Localization
<locale>	<codecvt>	<clocale>
Containers
<span> <array> <vector>	<deque> <forward_list> <list>	<map> <set> <queue>	<unordered_map> <unordered_set> <stack>
Iterators
<iterator>
Algorithms
<algorithm>	<execution>
Numerics
<complex> <random>	<valarray> <numeric>	<cfenv> <cmath>	<bit>
Input/Output
<iosfwd> <ios> <iomanip> <streambuf>	<istream> <ostream> <iostream>	<sstream> <fstream> <syncstream>	<cstdio> <cinttypes> <strstream>
Regular expressions
<regex>
Filesystem support
<filesystem>
Thread support
<thread> <atomic>	<mutex> <shared_mutex>	<condition_variable> <future>
C compatibility
<ciso646> <cstdalign>	<cstdbool> <ccomplex>	<ctgmath>

This header is part of the general utility library.

Includes
<string>
<iosfwd>
Classes
bitset	implements constant length bit array (class)
std::hash<std::bitset> (C++11)	hash support for std::bitset (class template specialization)
Functions
operator&operator|operator^	performs binary logic operations on bitsets (function template)
operator<<operator>>	performs stream input and output of bitsets (function template)

Synopsis

#include <string>
#include <iosfwd> // for istream, ostream

namespace std {
    template <size_t N> class bitset;

    // bitset operators:
    template <size_t N>
        bitset<N> operator&(const bitset<N>&, const bitset<N>&) noexcept;
    template <size_t N>
        bitset<N> operator|(const bitset<N>&, const bitset<N>&) noexcept;
    template <size_t N>
        bitset<N> operator^(const bitset<N>&, const bitset<N>&) noexcept;
    template <class charT, class traits, size_t N>
        basic_istream<charT, traits>&
        operator>>(basic_istream<charT, traits>& is, bitset<N>& x);
    template <class charT, class traits, size_t N>
        basic_ostream<charT, traits>&
        operator<<(basic_ostream<charT, traits>& os, const bitset<N>& x);

    // Hash support
    template <class T> struct hash;
    template <size_t N> struct hash<bitset<N> >;

}

Class std::bitset

template<size_t N> class bitset {
public:
    // bit reference:
    class reference {
        friend class bitset;
        reference() noexcept;
    public:
        ~reference() noexcept;
        reference& operator=(bool x) noexcept;          //  for b[i] = x;
        reference& operator=(const reference&) noexcept;//  for b[i] = b[j];
        bool operator~() const noexcept;                //  flips the bit
        operator bool() const noexcept;                 //  for x = b[i];
        reference& flip() noexcept;                     //  for b[i].flip();

    };

    //constructors:
    constexpr bitset() noexcept;
    constexpr bitset(unsigned long long val) noexcept;
    template<class charT, class traits, class Allocator>
        explicit bitset(
            const basic_string<charT,traits,Allocator>& str,
            typename basic_string<charT,traits,Allocator>::size_type pos = 0,
            typename basic_string<charT,traits,Allocator>::size_type n =
                basic_string<charT,traits,Allocator>::npos,
            charT zero = charT('0'), charT one = charT('1'));
    template <class charT>
        explicit bitset(
            const charT* str,
            typename basic_string<charT>::size_type n = basic_string<charT>::npos,
            charT zero = charT('0'), charT one = charT('1'));

    // bitset operations:
    bitset<N>& operator&=(const bitset<N>& rhs) noexcept;
    bitset<N>& operator|=(const bitset<N>& rhs) noexcept;
    bitset<N>& operator^=(const bitset<N>& rhs) noexcept;
    bitset<N>& operator<<=(size_t pos) noexcept;
    bitset<N>& operator>>=(size_t pos) noexcept;
    bitset<N>& set() noexcept;
    bitset<N>& set(size_t pos, bool val = true);
    bitset<N>& reset() noexcept;
    bitset<N>& reset(size_t pos);
    bitset<N> operator~() const noexcept;
    bitset<N>& flip() noexcept;
    bitset<N>& flip(size_t pos);

    // element access:
    constexpr bool operator[](size_t pos) const; // for b[i];
    reference operator[](size_t pos); // for b[i];


    unsigned long to_ulong() const;
    unsigned long long to_ullong() const;
    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;

    size_t count() const noexcept;
    constexpr size_t size() noexcept;

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

    bool test(size_t pos) const;
    bool all() const noexcept;
    bool any() const noexcept;
    bool none() const noexcept;

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