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std::priority_queue<T,Container,Compare>::push

void push( const value_type& value );
 
void push( value_type&& value );
 (since C++11)

Pushes the given element value to the priority queue.

1) Effectively calls c.push_back(value); std::push_heap(c.begin(), c.end(), comp);
2) Effectively calls c.push_back(std::move(value)); std::push_heap(c.begin(), c.end(), comp);

Parameters

value - the value of the element to push

Return value

(none).

Complexity

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

Example

#include <iostream>
#include <queue>
 
struct Event
{
    int priority{};
    char data{' '};
 
    friend bool operator< (Event const& lhs, Event const& rhs)
    {
        return lhs.priority < rhs.priority;
    }
 
    friend std::ostream& operator<< (std::ostream& os, Event const& e)
    {
        return os << '{' << e.priority << ", '" << e.data << "'}";
    }
};
 
int main()
{
    std::priority_queue<Event> events;
 
    std::cout << "Fill the events queue:\t";
 
    for (auto const e: {Event{6,'L'}, {8,'I'}, {9,'S'}, {1,'T'}, {5,'E'}, {3,'N'}})
    {
        std::cout << e << ' ';
        events.push(e);
    }
 
    std::cout << "\n" "Process events:\t\t";
 
    for (; !events.empty(); events.pop())
    {
        Event const& e = events.top();
        std::cout << e << ' ';
    }
}

Output:

Fill the events queue:  {6, 'L'} {8, 'I'} {9, 'S'} {1, 'T'} {5, 'E'} {3, 'N'}
Process events:         {9, 'S'} {8, 'I'} {6, 'L'} {5, 'E'} {3, 'N'} {1, 'T'}

See also

(C++11)
 constructs element in-place and sorts the underlying container
(public member function)
removes the top element
(public member function)

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https://en.cppreference.com/w/cpp/container/priority_queue/push