std::vector<bool>

 

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std::vector<bool>

Member functions
vector::vector vector::~vector vector::operator=	vector::assign vector::get_allocator
Element access
vector::at vector::operator[]	vector::front vector::back
Iterators
vector::beginvector::cbegin (C++11) vector::endvector::cend (C++11)	vector::rbeginvector::crbegin (C++11) vector::rendvector::crend (C++11)
Capacity
vector::empty vector::size vector::max_size	vector::reserve vector::capacity
Modifiers
vector::clear vector::insert vector::emplace (C++11)   vector::erase vector::push_back	vector::emplace_back (C++11) vector::pop_back vector::resize vector::swap
std::vector<bool> specific
vector<bool>::flip
vector<bool>::swap
Non-member functions
operator==operator!=operator<operator>operator<=operator>=operator<=> (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)(C++20)	swap(std::vector<bool>) erase(std::vector<bool>)erase_if(std::vector<bool>) (C++20)(C++20)
Helper classes
hash<std::vector<bool>> (C++11)
Deduction guides(C++17)

 

Defined in header <vector>
template<class Allocator = std::allocator<bool>> class vector<bool, Allocator>;

std::vector<bool> is a space-efficient specialization of std::vector for the type bool.

The manner in which std::vector<bool> is made space efficient (as well as whether it is optimized at all) is implementation defined. One potential optimization involves coalescing vector elements such that each element occupies a single bit instead of a byte-sized bool.

std::vector<bool> behaves similarly to std::vector, but in order to be space efficient, it:

• Does not necessarily store its data in a single contiguous chunk of memory.
• Exposes std::vector<bool>::reference as a method of accessing individual bits.
• Does not use std::allocator_traits::construct to construct bit values.

Member types

Template:cpp/container/dcl list value typeTemplate:cpp/container/dcl list allocator typeTemplate:cpp/container/dcl list size typeTemplate:cpp/container/dcl list difference typeTemplate:cpp/container/dcl list const referenceTemplate:cpp/container/dcl list pointerTemplate:cpp/container/dcl list const pointerTemplate:cpp/container/dcl list iteratorTemplate:cpp/container/dcl list const iteratorTemplate:cpp/container/dcl list reverse iteratorTemplate:cpp/container/dcl list const reverse iterator

Member type	Definition
reference	proxy class representing a reference to a single bool (class)

Member functions

Template:cpp/container/dcl list constructorTemplate:cpp/container/dcl list destructorTemplate:cpp/container/dcl list operator=Template:cpp/container/dcl list assignTemplate:cpp/container/dcl list get allocatorTemplate:cpp/container/dcl list atTemplate:cpp/container/dcl list operator atTemplate:cpp/container/dcl list frontTemplate:cpp/container/dcl list backTemplate:cpp/container/dcl list beginTemplate:cpp/container/dcl list endTemplate:cpp/container/dcl list rbeginTemplate:cpp/container/dcl list rendTemplate:cpp/container/dcl list emptyTemplate:cpp/container/dcl list sizeTemplate:cpp/container/dcl list max sizeTemplate:cpp/container/dcl list reserveTemplate:cpp/container/dcl list capacityTemplate:cpp/container/dcl list clearTemplate:cpp/container/dcl list insertTemplate:cpp/container/dcl list eraseTemplate:cpp/container/dcl list push backTemplate:cpp/container/dcl list pop backTemplate:cpp/container/dcl list resizeTemplate:cpp/container/dcl list swapTemplate:cpp/container/vector bool/dcl list flipTemplate:cpp/container/vector bool/dcl list swap

Element access

Iterators

Capacity

Modifiers

vector<bool> specific modifiers

Non-member functions

Template:cpp/container/dcl list operator cmpTemplate:cpp/container/dcl list swap2

Helper classes

Template:cpp/container/vector bool/dcl list hash

Notes

If the size of the bitset is known at compile time, std::bitset may be used, which offers a richer set of member functions. In addition, boost::dynamic_bitset exists as an alternative to std::vector<bool>.

std::vector<bool> does not not fulfill all container requirements because of proxy class std::vector<bool>::reference. Because of this proxy reference, the std::vector<bool>::iterator cannot be a Template:concept. Therefore this iterator does not fulfill the Template:concept requirement of some algorithms as for std::search. Consequently, this misuse can cause many problems... Moreover, depending on the implementation, they may not be a compile error or even a run-time error! (reference: boost)