#include

#define ll long long

#define mod 1000000007

using namespace std;

//熟悉一下优先队列的基本用法

int main()

{

int n;cin>>n;

priority_queueq;

int j;

for(int i=1;i<=n;i++)

{

cin>>j;

q.push(j);

}

while(!q.empty())

{

cout<

q.pop();

}

return 0;

}

java：

import java.math.BigInteger;

import java.util.*;

public class CF470C {

public static void main(String[] args) {

PriorityQueue queue = new PriorityQueue();

queue.add("C");

queue.add("C++");

queue.add("Python");

queue.add("Java");

// Printing the most priority element

System.out.println("Head value using peek function:"

+queue.peek());

// Printing all elements

System.out.println("The queue elements");

Iterator itr=queue.iterator();

while(itr.hasNext())

System.out.println(itr.next());

// Removing the top priority element (or head) and

// printing the modified pQueue

queue.poll();

System.out.println("After removing an element" +

"with poll function:");

Iterator itr2 = queue.iterator();

while (itr2.hasNext())

System.out.println(itr2.next());

// // Removing Java

queue.remove("C");

System.out.println("after removing Java with" +

" remove function:");

Iterator itr3 = queue.iterator();

while (itr3.hasNext())

System.out.println(itr3.next());

// // Check if an element is present

boolean b=queue.contains("C");

System.out.println ( "Priority queue contains C" +

"ot not?: " + b);

// get objects from the queue in an array and

// print the array

Object[]arr=queue.toArray();

System.out.println("Value in array: ");

for(int i=0;i

System.out.println("Value: "+arr[i].toString());

}

}

注意：Java中的优先队列没有排序功能，若要排序，请用：

As you can see in the PriorityQueue javadoc: The Iterator provided in method iterator() is not guaranteed to traverse the elements of the priority queue in any particular order. If you need ordered traversal, consider using Arrays.sort(pq.toArray()). That's because java.util.PriorityQueue implements a binary heap.

应用：

Applications :

Implementing Dijkstra’s and Prim’s algorithms.

https://www.geeksforgeeks.org/priority-queue-class-in-java-2/

例题：

//��CF 947B

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

using namespace std;

typedef long long LL;

typedef double DB;

const int N = 111111;

int n,a[N],b[N];

priority_queue,greater > Q;

int main()

{

int i,x;

LL w,ans;

scanf("%d",&n);

for(i=1;i<=n;i=i+1)

scanf("%d",a+i);

for(i=1;i<=n;i=i+1)

scanf("%d",b+i);

w=0,x=0;

for(i=1;i<=n;i=i+1){

ans=0;

Q.push(w+a[i]);

x++;

while(!Q.empty()&&Q.top()<=w+b[i]){

ans+=Q.top()-w;

Q.pop();

x--;

}

w+=b[i];

ans+=(LL)b[i]*x;

cout<

}

return 0;

}