std::swap(std::vector)

 

C++

Compiler support

Freestanding and hosted

Language

Standard library

Standard library headers

Named requirements

Feature test macros(C++20)

Language support library

Concepts library(C++20)

Diagnostics library

Memory management library

Metaprogramming library(C++11)

General utilities library

Containers library

Iterators library

Ranges library(C++20)

Algorithms library

Strings library

Text processing library

Numerics library

Date and time library

Input/output library

Filesystem library(C++17)

Concurrency support library(C++11)

Execution control library(C++26)

Technical specifications

Symbols index

External libraries

 

Containers library

node-handle (C++17)

Sequence

array (C++11)

vector

vector<bool>

inplace_vector (C++26)

hive (C++26)

deque

forward_list (C++11)

list

Associative

set

multiset

map

multimap

Unordered associative

unordered_set (C++11)

unordered_multiset (C++11)

unordered_map (C++11)

unordered_multimap (C++11)

Adaptors

stack

queue

priority_queue

flat_set (C++23)

flat_multiset (C++23)

flat_map (C++23)

flat_multimap (C++23)

Views

span (C++20)

mdspan (C++23)

Tables

Iterator invalidation

Member function table

Non-member function table

 

std::vector

Member types
Member functions
vector::vector vector::~vector vector::operator= vector::assign vector::assign_range (C++23)   vector::get_allocator Element access vector::operator[] vector::at vector::data 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 vector::shrink_to_fit (DR*) Modifiers vector::clear vector::erase vector::insert vector::insert_range (C++23) vector::append_range (C++23) vector::emplace (C++11) vector::emplace_back (C++11) vector::push_back vector::pop_back vector::resize vector::swap
Non-member functions
operator==operator<=> (C++20) swap(std::vector) erase(std::vector)erase_if(std::vector) (C++20)(C++20)	operator!=operator<operator>operator<=operator>= (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)
Deduction guides(C++17)

 

Defined in header <vector>
template<class T, class Alloc > void swap(std::vector<T, Alloc>& lhs,            std::vector<T, Alloc>& rhs );		(until C++17)
template<class T, class Alloc > void swap(std::vector<T, Alloc>& lhs,            std::vector<T, Alloc>& rhs )                noexcept(/* see below */);		(since C++17) (constexpr since C++20)

Specializes the std::swap algorithm for std::vector. Swaps the contents of lhs and rhs. Calls lhs.swap(rhs).

Parameters

lhs, rhs

-

containers whose contents to swap

Return value

(none)

Complexity

Constant.

Exceptions

noexcept specification:   noexcept(noexcept(lhs.swap(rhs)))

(since C++17)

Example

Run this code

#include <algorithm>#include <iostream>#include <vector>   int main(){std::vector<int> alice{1, 2, 3};std::vector<int> bob{7, 8, 9, 10};   auto print =[](constint& n){std::cout<<' '<< n;};   // Print state before swapstd::cout<<"Alice:";std::for_each(alice.begin(), alice.end(), print);std::cout<<"\nBobby:";std::for_each(bob.begin(), bob.end(), print);std::cout<<'\n';   std::cout<<"-- SWAP\n";std::swap(alice, bob);   // Print state after swapstd::cout<<"Alice:";std::for_each(alice.begin(), alice.end(), print);std::cout<<"\nBobby:";std::for_each(bob.begin(), bob.end(), print);std::cout<<'\n';}

Output:

Alice: 1 2 3 Bobby: 7 8 9 10 -- SWAP Alice: 7 8 9 10 Bobby: 1 2 3

See also

swap	swaps the contents (public member function)