算法导论笔记

@Test
    public void insertionSort() {
        Integer[] a = {5,9,3,4,2,1,6,8,10,7,65,54,85,32,15,94,75,62,34,76,45,32,85};
        for(int i = 1; i<a.length; i++){
            int key = a[i];
            int j = i - 1;
            //循环不变式
            while (j >= 0 && a[j]>key){
                a[j+1] = a[j];
                a[j] = key;
                j = j-1;
            }
        }
        System.out.print(Arrays.toString(a));
    }

　　

插入算法的重点：循环不变式、适合少量数据