std::swap(std::set)

 

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std::set

Member functions

set::set set::~set            set::operator= set::get_allocator

Iterators set::beginset::cbegin (C++11) set::endset::cend (C++11) set::rbeginset::crbegin (C++11)   set::rendset::crend (C++11) Capacity set::size set::max_size set::empty Observers set::key_comp set::value_comp Modifiers set::clear set::erase set::swap set::extract (C++17) set::merge (C++17) set::insert set::insert_range (C++23) set::emplace (C++11) set::emplace_hint (C++11) Lookup set::count set::find set::contains (C++20)    set::equal_range set::lower_bound set::upper_bound

Non-member functions

operator==operator<=> (C++20) std::swap(std::set) erase_if(std::set) (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 <set>
template< class Key, class Compare, class Alloc > void swap( std::set<Key, Compare, Alloc>& lhs,            std::set<Key, Compare, Alloc>& rhs );		(until C++17)
template< class Key, class Compare, class Alloc > void swap( std::set<Key, Compare, Alloc>& lhs,            std::set<Key, Compare, Alloc>& rhs )                noexcept(/* see below */);		(since C++17)

Specializes the std::swap algorithm for std::set. 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 <set>
 
int main()
{
    std::set<int> alice{1, 2, 3};
    std::set<int> bob{7, 8, 9, 10};
 
    auto print = [](const int& n) { std::cout << ' ' << n; };
 
    // Print state before swap
    std::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 swap
    std::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)