std::priority_queue push() 方法

自 C++11 起

// (1) Non const version only
void push( const value_type& value );

// (2) Non const version only
void push( value_type&& value );

直到 C++11

// (1) Non const version only
void push( const value_type& value );

将给定的元素值推送到优先队列的末尾。

• (1) 实际上调用

  c.push_back(value);
  std::push_heap(c.begin(), c.end(), comp);
• (1) 实际上调用

  c.push_back(std::move(value));
  std::push_heap(c.begin(), c.end(), comp);

参数

• value - 要推入的元素的值

返回值

(无)

复杂度

对底层容器的 push_back 操作的对数级比较次数加上其复杂度。

示例

Main.cpp

#include <queue>
#include <iostream>
 
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:\n";
 
    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:\n";
 
    for (; !events.empty(); events.pop()) {
        Event const& e = events.top();
        std::cout << e << ' ';
    }
}

输出

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' }