NAME¶

std::priority_queue::emplace - std::priority_queue::emplace

Synopsis¶

template< class... Args > (since C++11)
void emplace( Args&&... args );

Pushes a new element to the priority queue. The element is constructed in-place,
i.e. no copy or move operations are performed. The constructor of the element is
called with exactly the same arguments as supplied to the function.

Effectively calls

c.emplace_back(std::forward<Args>(args)...);
std::push_heap(c.begin(), c.end(), comp);

Parameters¶

args - arguments to forward to the constructor of the element

Return value¶

(none)

Complexity¶

Logarithmic number of comparisons plus the complexity of Container::emplace_back.

Example¶

// Run this code

#include <iostream>
#include <queue>

struct S
{
int id;

S(int i, double d, std::string s) : id{i}
{
std::cout << "S::S(" << i << ", " << d << ", \"" << s << "\");\n";
}
friend bool operator< (S const& x, S const& y) { return x.id < y.id; }
};

int main()
{
std::priority_queue<S> queue;
queue.emplace(42, 3.14, "C++");
std::cout << "id: " << queue.top().id << '\n';
}

Output:¶

S::S(42, 3.14, "C++")
id = 42

See also¶

push inserts element and sorts the underlying container
(public member function)
pop removes the top element
(public member function)