Code interview:获取数组中最小的K个数

获取数组中最小的K个数，利用堆完成。

public class MinKNum {

    public void createHeap(int[]heap){
        int len = heap.length;

        int i = len >> 1;

        while(i >= 1){
            sink(heap,i);
            i--;
        }
    }


    public void sink(int[]heap,int i){

        int len = heap.length;
        int lChild = i << 1;

        if (lChild >= len)
            return;
        int rChild = i << 1 + 1;

        int next;

        if (rChild >= len) {
            next = lChild;
        } else {
            next = heap[lChild] >= heap[rChild] ? lChild:rChild;
        }

        if (heap[i] < heap[next]) {
            swap(heap,i,next);
            sink(heap,next);
        }

    }

    public void swap(int[]heap,int i,int j){
        int tmp = heap[i];
        heap[i] = heap[j];
        heap[j] = tmp;
    }

    public int[] getMinTopK(int[]array,int k){
        int len = array.length;

        if(len<=k){
            return array;
        }

        int[] heap = new int[k+1];
        for(int i=0;i<k;i++){
            heap[i+1] = array[i];
        }

        createHeap(heap);

        for(int i=k;i<len;i++){
            if(heap[1]>array[i]){
                heap[1] = array[i];
                sink(heap,1);
            }
        }

        return heap;
    }

    public static void main(String[]args){
        MinKNum minKNum = new MinKNum();
        int[] tops = minKNum.getMinTopK(new int[]{1,98,12,32,15,54,26,97,19,32,12},5);

        for(int n:tops){
            System.out.println(n);
        }
    }