std::bitset<N>::size

 

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std::bitset

Member types
bitset::reference
Member functions
bitset::bitset
bitset::operator==bitset::operator!= (until C++20)
Element access
bitset::operator[]
bitset::test
bitset::allbitset::anybitset::none (C++11)
bitset::count
Capacity
bitset::size
Modifiers
bitset::operator&=bitset::operator|=bitset::operator^=bitset::operator~
bitset::operator<<=bitset::operator>>=bitset::operator<<bitset::operator>>
bitset::set
bitset::reset
bitset::flip
Conversions
bitset::to_string
bitset::to_ulong
bitset::to_ullong (C++11)
Non-member functions
operator&operator|operator^	operator<<operator>>
Helper classes
std::hash (C++11)

 

std::size_t size() const;		(noexcept since C++11) (constexpr since C++11)

Returns the number of bits that the bitset holds.

Parameters

(none)

Return value

number of bits that the bitset holds, i.e. the template parameter N.

Example

Run this code

#include <bitset>
#include <iostream>

int main()
{
    std::cout << std::bitset<0x400>().size() << '\n';
}

Output:

1024

See also

count

returns the number of bits set to true (public member function)