Algs4-2.1.11希尔排序序列改为存数组

2.1.11将希尔排序中实时计算递增序列改为预先计算并存储在一个数组中。public class Shell2{??? public static void sort(Comparable[] a)??? {??????? int N=a.length;??????? int h=1;??????? int[] SN=new int[20];??????? int hMaxIndex=0;??????? while (h<N/3) ??????? {?????????? SN[hMaxIndex]=h;??????????? h=3*h+1;??????????? hMaxIndex++;??????? }??????? ??????? for (int hIndex=hMaxIndex;hIndex>0;hMaxIndex--)??????? {??????????? h=SN[hIndex];??????????? for (int i=h;i<N;i++)??????????? {??????????????? for (int j=i;j>=h && less(a[j],a[j-h]);j-=h)??????????????????? exch(a,j,j-h);??????????? }??????? }??? }??? ??? private static boolean less(Comparable v,Comparable w)??? { return v.compareTo(w)<0;}??? ??? private static void exch(Comparable[] a,int i,int j)??? {??????? Comparable t=a[i];??????? a[i]=a[j];??????? a[j]=t;??? }??? ??? private static void show(Comparable[] a)??? {??????? for (int i=0;i<a.length;i++)??????????? StdOut.print(a[i]+" ");??????? StdOut.println();??? }??? ??? public static boolean isSorted(Comparable[] a)??? {??????? for (int i=0;i<a.length;i++)??????????? if(less(a[i],a[i-1])) return false;??????? return true;??? }??? ?? }