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

移除优先队列的顶部元素。实际上调用了 std:: pop_heap ( c. begin ( ) , c. end ( ) , comp ) ; c. pop_back ( ) ; 。

参数

(无)

返回值

(无)

复杂度

比较次数的对数加上 Container :: pop_back 的复杂度。

示例

#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 << "填充事件队列：\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处理事件：\t\t";
    for (; !events.empty(); events.pop())
    {
        Event const& e = events.top();
        std::cout << e << ' ';
    }
    std::cout << '\n';
}

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'}

参阅