priority_queue

1.priority_queue

 

#include <iostream>
#include <queue>
using namespace std;
void priority_queue_init()
{
    priority_queue<int> p1 ; //默认情况下 是 最大值优先级队列 
    priority_queue<int , vector<int>, less<int> > p2; //提前定义好的预定义函数  谓词
    priority_queue<int , vector<int>, greater<int> >  p3; //最小值优先级队列

    p1.push(33);
    p1.push(11);
    p1.push(55);
    p1.push(22);

    cout << "队头元素:" << p1.top() <<endl;
    cout << "队列的大小:" << p1.size() << endl;

    while (p1.size() > 0 )
    {
        cout << p1.top() << " ";
        p1.pop();
    }

    cout << "测试 最小值优先级队列 " << endl;

    p3.push(33);
    p3.push(11);
    p3.push(55);
    p3.push(22);

    cout << " 最小值优先级队列 队头元素:" << p3.top() <<endl;
    cout << " 最小值优先级队列 队列的大小:" << p3.size() << endl;

    while (p3.size() > 0 )
    {
        cout << p3.top() << " ";
        p3.pop();
    }
}
int main()
{
    priority_queue_init();
    return 0;
}