FreeBSD Manual Pages
std::bitset(3) C++ Standard Libary std::bitset(3) NAME std::bitset - std::bitset Synopsis Defined in header <bitset> template< std::size_t N > class bitset; The class template bitset represents a fixed-size sequence of N bits. Bitsets can be manipulated by standard logic operators and converted to and from strings and integers. For the purpose of the string representation and of naming directions for shift operations, the sequence is thought of as having its lowest indexed elements at the right, as in the binary representation of integers. bitset meets the requirements of CopyConstructible and CopyAssigna- ble. All member functions of std::bitset are constexpr: it is possible to create and use std::bitset objects in the evaluation of a constant (since C++23) expression. Template parameters N - the number of bits to allocate storage for Member types reference proxy class representing a reference to a bit (class) Member functions constructor constructs the bitset (public member function) operator== compares the contents operator!= (public member function) (removed in C++20) Element access operator[] accesses specific bit (public member function) test accesses specific bit (public member function) all checks if all, any or none of the bits are set to true any (public member function) none count returns the number of bits set to true (public member function) Capacity size returns the number of bits that the bitset holds (public member function) Modifiers operator&= operator|= performs binary AND, OR, XOR and NOT operator^= (public member function) operator~ operator<<= operator>>= performs binary shift left and shift right operator<< (public member function) operator>> set sets bits to true or given value (public member function) reset sets bits to false (public member function) flip toggles the values of bits (public member function) Conversions to_string returns a string representation of the data (public member function) to_ulong returns an unsigned long integer representation of the data (public member function) to_ullong returns an unsigned long long integer representa- tion of the data (C++11) (public member function) Non-member functions operator& performs binary logic operations on bitsets operator| (function template) operator^ operator<< performs stream input and output of bitsets operator>> (function template) Helper classes std::hash<std::bitset> hash support for std::bitset (C++11) (class template specialization) Notes If the size of a bit-set is not known at compile time, or it is nec- essary to change its size at run-time, the dynamic types such as std::vector<bool> or boost::dynamic_bitset<> may be used instead. Feature-test macro Value Std Feature __cpp_lib_constexpr_bitset 202207L (C++23) A more constexpr std::bitset __cpp_lib_bitset 202306L (C++26) Interfacing std::bitset with std::string_view Example // Run this code #include <bitset> #include <cassert> #include <cstddef> #include <iostream> int main() { typedef std::size_t length_t, position_t; // the hints // constructors: constexpr std::bitset<4> b1; constexpr std::bitset<4> b2{0xA}; // == 0B1010 std::bitset<4> b3{"0011"}; // can also be constexpr since C++23 std::bitset<8> b4{"ABBA", length_t(4), /*0:*/'A', /*1:*/'B'}; // == 0B0000'0110 // bitsets can be printed out to a stream: std::cout << "b1:" << b1 << "; b2:" << b2 << "; b3:" << b3 << "; b4:" << b4 << '\n'; // bitset supports bitwise operations: b3 |= 0b0100; assert(b3 == 0b0111); b3 &= 0b0011; assert(b3 == 0b0011); b3 ^= std::bitset<4>{0b1100}; assert(b3 == 0b1111); // operations on the whole set: b3.reset(); assert(b3 == 0); b3.set(); assert(b3 == 0b1111); assert(b3.all() && b3.any() && !b3.none()); b3.flip(); assert(b3 == 0); // operations on individual bits: b3.set(position_t(1), true); assert(b3 == 0b0010); b3.set(position_t(1), false); assert(b3 == 0); b3.flip(position_t(2)); assert(b3 == 0b0100); b3.reset(position_t(2)); assert(b3 == 0); // subscript operator[] is supported: b3[2] = true; assert(true == b3[2]); // other operations: assert(b3.count() == 1); assert(b3.size() == 4); assert(b3.to_ullong() == 0b0100ULL); assert(b3.to_string() == "0100"); } Output: b1:0000; b2:1010; b3:0011; b4:00000110 See also vector<bool> space-efficient dynamic bitset (class template specialization) Bit manipulation (C++20) utilities to access, manipulate, and process individual bits and bit sequences http://cppreference.com 2024.06.10 std::bitset(3)
NAME | Synopsis | Template parameters | Member types | Member functions | Element access | Capacity | Modifiers | Conversions | Non-member functions | Helper classes | Notes | Example | Output: | See also
Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=std::bitset&sektion=3&manpath=FreeBSD+Ports+15.1.quarterly>