API
1.構造函數
PriorityQueue()
PriorityQueue(Collection<? extends E> c)
PriorityQueue(int initialCapacity)
PriorityQueue(int initialCapacity, Comparator<? super E> comparator)
PriorityQueue(PriorityQueue<? extends E> c)
PriorityQueue(SortedSet<? extends E> c)2.常用功能函數
| 方法名 | 功能描述 |
|---|---|
| add(E e) | 添加元素 |
| clear() | 清空 |
| contains(Object o) | 檢查是否包含當前參數元素 |
| offer(E e) | 添加元素 |
| peek() | 讀取元素，（不刪除） |
| poll() | 取出元素，（刪除） |
| remove(Object o) | 刪除指定元素 |
| size() |
返回長度 |
以上參考自：https://www.cnblogs.com/demingblog/p/6485193.html
// 代碼實現
import java.util.PriorityQueue;
public class priority_queue {
public static void main(String[] args) {
// TODO Auto-generated method stub
PriorityQueue<Integer> q = new PriorityQueue<>();
q.offer(3);
q.offer(1);
q.offer(2);
q.offer(4);
q.offer(5);
System.out.println("contains 3: " + q.contains(3));
System.out.println("remove 3: " + q.remove(3));
System.out.println("size: " + q.size());
while(!q.isEmpty()) {
Integer top = q.poll();
System.out.print(top + ", ");
}
System.out.println();
TestNode();
}
private static class Node implements Comparable<Node> {
int a, b;
public Node(int a, int b) {
this.a = a;
this.b = b;
}
@Override
public int compareTo(Node arg0) {
// TODO Auto-generated method stub
if(a == arg0.a) {
return b - arg0.b;
}
return a - arg0.a;
}
}
private static void TestNode() {
PriorityQueue<Node> q = new PriorityQueue<>();
q.offer(new Node(3, 1));
q.offer(new Node(2, 3));
q.offer(new Node(2, 1));
q.offer(new Node(4, 3));
while(!q.isEmpty()) {
Node top = q.poll();
System.out.print(top.a + ": " + top.b + ", ");
}
System.out.println();
}
}繼續加油~