std::swap(std::flat_map)
From cppreference.com
| Defined in header <flat_map>
|
||
friend void swap( std::flat_map& lhs, std::flat_map& rhs ) noexcept;
|
(since C++23) | |
Specializes the std::swap algorithm for std::flat_map. Swaps the contents of lhs and rhs. Calls lhs.swap(rhs).
Parameters
| lhs, rhs | - | containers whose contents to swap |
Return value
(none)
Complexity
Same as swapping the underlying containers.
Example
Run this code
#include <algorithm>
#include <iostream>
#include <flat_map>
int main()
{
std::flat_map<int, char> alice{{1, 'a'}, {2, 'b'}, {3, 'c'}};
std::flat_map<int, char> bob{{7, 'Z'}, {8, 'Y'}, {9, 'X'}, {10, 'W'}};
auto print = [](std::pair<const int, char>& n)
{
std::cout << ' ' << n.first << ':' << n.second;
};
// 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:a 2:b 3:c
Bobby: 7:Z 8:Y 9:X 10:W
-- SWAP
Alice: 7:Z 8:Y 9:X 10:W
Bobby: 1:a 2:b 3:c