最小的K个数

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输入n个整数，找出其中最小的K个数。例如输入4,5,1,6,2,7,3,8这8个数字，则最小的4个数字是1,2,3,4,。

import java.util.*;public class GetLeastNumbers {/** * @param args */ public  ArrayList<Integer> GetLeastNumbers_Solution(int [] input, int k) { ArrayList<Integer> result = new ArrayList<Integer>();       int length = input.length;       if(k>length||k==0){         return result;         }       PriorityQueue<Integer> maxHeap = new  PriorityQueue<Integer>(k,new Comparator<Integer>(){          public int compare(Integer o1,Integer o2){                  return o2.compareTo(o1);         }       });       for(int i = 0;i<length;i++){          if(maxHeap.size()!=k){              maxHeap.offer(input[i]);        }else if(maxHeap.peek()>input[i]){             Integer temp = maxHeap.poll();             temp = null;             maxHeap.offer(input[i]);             }           }           for(Integer integer:maxHeap) {                 result.add(integer);      }      return result;    }public static void main(String[] args) {// TODO Auto-generated method stubint []a={6,7,8,0,1,2,4,5,3};System.out.println(new GetLeastNumbers().GetLeastNumbers_Solution(a, 4));}}

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