算法笔记6：TopK问题——优先序列（基于数组、链表）_多链表找topk

基于有序数组的优先序列

/**
 * 基于有序数组的优先序列
 * @author XY
 *
 */
@SuppressWarnings("unchecked")
public class PriorityB<Key extends Comparable<Key>> {
   
private final int len_default=8;
	private Key[] pq;
	private int len;
	private int size;
	
	public PriorityB(){
   
		this.len=len_default+1;
		pq=(Key[])new Comparable[len];
		size=0;
	}
	public PriorityB(int len){
   
		this.len=len+1;
		pq=(Key[])new Comparable[len];
		size=0;
	}
	
	public PriorityB(Key[] key){
   
		this.len=key.length+1;
		pq=(Key[])new Comparable[len];
		for (int i = 0; i < key.length; i++) {
   
			insert(key[i]);
		}
		
	} 
	public void insert(Key a){
   
		pq[++size]=a;
		Key temp;
		int i=size;
		while(i>1 && less(pq[i], pq[i-1]) ){
   //数组越界的约束应该在任何条件的前面
			temp=pq[i];
			pq[i]=pq[i-1];
			pq[i-1]=temp;
			i--;
		}
	}
	public Key max(){
   
		return pq[size--];
	}
	public Key delMax(){
   
		if (size==0) 
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